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Skeletal System
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Skeletal system Theory
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Skeletal System
skeletal system
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION
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The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle
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It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.
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The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus
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Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.
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Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.
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Lower end : Articulated laterally with radius &
medialy with ulna
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Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.
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Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna
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Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones
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Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.
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Metacarpal bones : 5 bones, numbered
lateral to medial.
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Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur
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Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia
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Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula
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Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus
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Tarsus is made of seven tarsal bones arranged in two
rows
Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.
Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus
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Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges
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14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares
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Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.
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Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium
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It is also called brain box.
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It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1

Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone
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It is also called tongue bone.
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It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS
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There are 12 ribs on each side of thoracic cage
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First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)
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Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.
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Head - Has two parts. Lower part articulates with numerically corresponding vertebrae
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While the upper part articulates with higher vertebrae.
Costal Cartilages
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Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.
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Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM
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It is also called breast bone.
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It is 15 cm long in man.
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In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.
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It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina
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Presence of vertebral column is characteristic feature of vertebrates.
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It is also called spinal column or backbone.
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The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)
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In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae
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Cervical vertebrae are present in neck.
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They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).
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C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.
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Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae
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Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae
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Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae
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They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae
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These are 4 in number.
The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
SKELETAL SYSTEM
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
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25
26
27
28
29
30
31
32
33
34
35
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38
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40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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SKELETAL SYSTEM
DEFINITION AND INTRODUCTION




The hard protective or supportive part of the animal constitute skeletal system.
Study of skeleton is called Osteology or Skeletology.
Design of the skeleton depends on the animals mode of life.
Skeleton of different design are needed for the aquatic or terrestrial animals.
TYPES OF SKELETON
On the basis of location skeleton is of two typesExoskeleton
Endoskeleton
1. Exoskeleton

It is formed by secretion of the skin from epidermis.
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


It is always non living.
It is found in invertebrate as well as vertebrate.
It is composed of a non-living protein material called keratin or horn.
Epidermal exoskeleton
 Scales of reptiles are epidermal exoskeleton.
Exception - Crocodile and Tortoise. (mesodermal in origin)
 Beak, claws, horn hoof, feathers, hairs and nail are epidermal exoskeleton.
Dermal exoskeleton
Scales of fishes, crocodile and tortoise are dermal exoskeleton.
2. Endoskeleton



The endoskeleton includes hard parts present inside the body. The bone and cartilage are example of
endoskeleton.
It is always living.
Some invertebrate like, corals, cuttle fish and Echinodermata also possess endoskeleton.
TOTAL NUMBER OF BONES
In adult total number of bones are - 206
Axial skeleton
80
Appendicular skeleton
- 126
---------------206
---------------In neonates total number of bones are - 306
On the basis of the position of skeletal structure in the body Skeleton system is divided into 2 parts-
Shaft
Scapula
Head
Trochlea
Pubis
Obturator
foramen
Ischium
Shaft
Condyle
Ulna
Innominate
Clavicle
Glenoid cavity
Femur
Head
Ilium
Acetabulum
Pectoral girdle
Humerus
APPENDICULAR SKELETON
Patella
(knee cap)
Radius
Tibia
(Shin bone)
1
2 34
Carpals (8)
Metacarpals (5)
Fibula
Phalanges (14)
Tarsals (7)
5
Pectoral girdle and arm bones
(Anterior view)
5
4
32 1
Metatarsals (5)
Phalanges (14)
Half part of pelvic girdle and leg bones
(Anterior view)
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It is situated at lateral sides which extends outward from the principle axis. It is of composed of –
Girdle bones
–
Limb bones
Girdle bones
These are of 2 types(A) Pectoral girdle
(B) Pelvic girdle
(A) Pectoral girdle
Pectoral girdle is formed of two bones clavicle and
scapula.
Coracoia process
Superior
Clavicular facet
Acromion
Supraspinatus
Clavical is also called collar bone.
Scapula is also called shoulder bone or shoulder
blade. It is flat and triangular structure present at
the back of shoulder.
Scapula
Spine
Deltoid
Glenoid cavity
At the junction of clavical and scapula a depression
is found in the scapula called glenoid cavity.
In a glenoid cavity head of humerus fits to form
Scapula
Infraspinatus
shoulder joint.
(B) Pelvic girdle

It is also called hip girdle.

It is composed of 3 bones, which are as follows-
Ilium
-
Upper side
Pubis
-
Inner side
Ischium
-
Below the pubis
Fig. Scapula-Pectoral Girdle
Human pelvis from anterior aspect

At the junction of these 3 bones, a depression is found. Which is called acetabulum.
Femur fits in acetabulum to form hip joint.

The pelvic girdle of female are broader than male.
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Limb Bones
Bones of fore limb
In each fore limb total 30 bones are foundUpper arm -
Humerus
-
1
Fore arm
-
Radius (outer)
ulna (inner)
-
2
Wrist
-
Carpals
-
8
Palm
-
Metacarpals
-
5
Fingers
-
Phalanges
-
14
----------------30
----------------Phalangeal formula for human hand is 2,3,3,3,3.
The Humerus

Head : It articulates with the glenoid cavity of
scapula to form shoulder joint.

Deltoid ridge : Elevated rough part on the shaft
here deltoid muscle is attached.

Lower end : Articulated laterally with radius &
medialy with ulna

Coronoid fossa : depression just above the
anterior aspect of trochlea. It accomodated the
Coronoid process of ulna when elbow is flexed.

Olecranon f ossa : It accomodatee the
olecranon process of ulna when Elbow is
extended.
The Radius & Ulna

Radius : Its head is disc shaped, covered with
hyaline cartilage. it’s superior concave surface
articulates with the capitulum of humerus at
the elbow joint.

Circumference of head is also articular, it fits
into socket formed by the radial notch of the
ulna to form radioulanar joint.
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
Olecranon process : Projects upwards from
shaft of ulna. It is responsible for making
elbow joint hinge.
Carpal Bones

Proximal Row : From lateral to medial Scaphoid, lunate, triquetrum, pisciform

Distal Row : Trapezium, trapezoid, capitate,
Hammate.

Metacarpal bones : 5 bones, numbered
lateral to medial.

Phalanges : There are 14 phalanges in each
hand . 3 for each finger & for the thumb.
Bones of hind limb
In each hind limb total 30 bones are found.
Thigh
- Femur
- 1
Shank
- Tibia (inner)
- 2
Fibula (outer)
Ankle
- Tarsals
- 7
In step
- Metatarsal
- 5
Toes
- Phalanges
- 14
Knee joint - Patella ( Knee cap) - 1
----------------30
-----------------
Femur




Strongest heaviest and largest bone
Articulates with acetabulum to form the hip
joint.
Lower end of femur is widely expanded to
form two large condyles, one medial & one
lateral.
Greater and lesser trochanter are rough
projections to prov ide attachement to
muscles.
Tibia




Medial & larger bone of the leg.
Upper end : Expanded from side to side fo from two
large condyles.
Medial condyle : Its superior surface articulates
with medial condyle of femur.
Lateral condyle : Superior surface of condyle
articulates with lateral condyle of femur.
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Fibula


Lateral & smaller bone of the leg.
Its upper end articulates with the lateral condyle of
tibia.
Tarsus

Tarsus is made of seven tarsal bones arranged in two
rows

Proximal row : Talus above, Navicular in between and
Calcaneum below. Tarsal bones are larger &
stronger than carpal bones becuase they have to
support & distribute body weight.
Talus is second largest tarsal bone, lies between tibia
above & calcaneum below.

Calcaneum : Largest tarsal bone, forms the prominence
of heal.
Distal row : Four tarsal bones lying side by side (three
cuneiform and one cuboid)
Meta tarsus

Made of 5 meta tarsal bones which are numbered medial to lateral.
Phalanges



14 Phalanges, 2 for great tow & 3 each for each othe four toes.
As compared to Phalanges of hand these are small in size.
Phalangeal formula for human foot is 2, 3, 3, 3, 3
AXIAL SKELETON
It is present on the median longitudinal axis of the body. It consists of – Skull
– Ribs
–
Sternum
–
Vertebral column
SKULL
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Internal nares

Skull with two occipital condyles is called dicondylic. Human skull is dicondylic.



Skull is formed of 29 bones.
In rabbit 53 bones are found in skull.
Skull is composed of 4 portions.
(a) Cranium
(b) Face
(c) Hyoid
(d) Sensory capsule
(A) Cranium




It is also called brain box.
It is large and hollow round part of skull which encloses and protects the brain in the cranial cavity.
It has large opening foramen magnum at the posterior end , through which brain is continuous with
spinal cord.
Cranium is composed of 8 bones, which are as follows :
Frontal
- 1
Parietals
Temporal
Occipital
Sphenoid
Ethmoid

- 2
- 2
- 1
- 1
- 1
--------------8 bones
---------------
These bones are joined by immovable fibrous joints called Sutures.
Coronal Suture lies between frontal and parietal.
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Lambdoidal suture lies between parietal and occipital bones.
Sella Turcica - depression in sphenoid bone of skull that lodges pituitary body.
largest foramen - foramen magnun which is present below brain box, through it the spinal chord
comes out.
(B) Face
Face is composed of 14 bones which are as follows Maxillae
-
2
Palatine
-
2
Nasals
-
2
Lacrymals
-
2
Inferior turbinal
-
2
Zygomatic/malar bones
-
2
Vomer
-
1
Maldible
-
1
-----------------14 bones
-----------------Note :
Mandible is movable to allow mastication and speech.(Only Movable bone apart from ear ossicles.) In its
posterior part a pair of condyle are present which fit in the cavity of temporal bone, so the lower jaw attaches
with the cranium. This type of suspension is called craniostylic.
(C) Hyoid bone

It is also called tongue bone.

It is situated in the wall of the upper part of the throat, just above the larynx.
(D) Sensory capsule
Ear is surrounded by bony auditory capsules, middle ear has 3 movable ear ossicles
(i) Maleus (Modification of articular bone)
(ii) Incus (Modification of Quadrate bone)
(iii) Stapes (smallest bone of body) modification of Hyomandibular bone.
RIBS

There are 12 ribs on each side of thoracic cage

First 7 which are connected throuhg cartilage to the sternum are called True Ribs.
(Vertebrosternal ribs)

Remaining 5 are False Ribs, out of these cartilage of the 8th, 9th & 10th ribs are joined to the next
higher cartilage, 8th, 9th, 10th are called Vertebrochondral ribs. The anterior ends of 11th & 12th ribs
are free & are called floating ribs.
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.

Head - Has two parts. Lower part articulates with numerically corresponding vertebrae

While the upper part articulates with higher vertebrae.
Costal Cartilages

Unossified anterior parts of ribs made of hyaline cartilage. These contribute to the elasticity of thoracic
wall.

Medial ends of CC of first seven ribs are directly attached to sternum.
8th, 9th & 10th CC articulate with one another. The cartilage of 11th & 12th ribs are small. Theri ventral
end are free and lie in the muscle of abdominal wall.
Note : Like human in rabbit also 12 pairs of ribs are found.

STERNUM

It is also called breast bone.

It is 15 cm long in man.

In embryo sternum is made up of a series of bone called sternebra. In rabbit there is 7 sternebra while
in human there is 3 sternebra.

It is composed of 3 parts Manubrium
- Upper part
Body
- Middle part
(It is largest part)
Cartilaginous Xiphoid - Lower part
(Xiphisternum)
Note : Sternum is absent in fishes.
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VERTEBRAL COLUMN
Atlas
Axis
1
Cervical
2
curve
3
4
Centrum
5
6
7
1
2
3
Facets
for ribs
Thoracic
curve
Centrum
Neural
spine Cervical vertebrae
(1–7)
(Neck region)
4
5
Thoracic vertebrae
(1–12)
(Chest region)
6
7
8
9
10
11
12
Centrum
Neural
spine
1
2
Neural
spine
Lumbar 3
curve 4
5
Sacral
curve
General facts
Lumbar vertebrae
(1–5 )
(Lower back)
Scaral vertebrae
(Pelvis)
(5 fused)
Coccygeal
vertebrae
(4 fused)
Fig.: Human vertebra with intervertebral foramina

Presence of vertebral column is characteristic feature of vertebrates.

It is also called spinal column or backbone.

The component of vertebral column are called vertebrae. Vertebrae of man is acoelus (centrum is flat with
cavity)

In between vertebrae pads are found which are composed of fibrocartilage, called intervertebral pads.
These pads or disc acts as shock absorber.
Vertebral formula of man
The vertebral formula is C7T12L5S(5)Co(4) = 33 vertebrae.
Vertebral formula of rabbit
The vertebral formula is C7T12L7S4Co16 = 46 vertebrae.
Basic structure of vertebrae
(i) A vertebrae is typically a bony ring.
(ii) The two main portion of vertebrae is disc like centrum or body and neural arch.
(iii) Within neural arch a hole is found is called vertebral foramen. The vertebral formen of all the
vertebrae when intact form a vertebral canal, that encloses the spinal cord.
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Note :
Centrum of man is flat with no cavity, such centrum is called Acoelus or Amphiplatyn.
Functions of vertebral column
(i)
(ii)
(iii)
(iv)
It
It
It
It
encloses and protects the spinal cord.
carries the weight of the body.
helps in upright posture and locomotion.
helps in free movement of the head.
Groups of vertebrae
The vertebrae of vertebral column can be put in 5 groups, according to their location, which are as follows-
(I) Cervical vertebrae

Cervical vertebrae are present in neck.

They are 7 in number. In most mammal number of cervical vertebrae is 7
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
All cervial vertebrae have apertures in their transverse process (Foramina transversalis which form
vertebraterial canal on either side for vertebral artery to pass through to supply brain & posterior spinal
cord).

C1 & C2 = Atypical, C3 to C7 = typical

Atlas : - Transverse process are wing like, centrum is absent, Ring like.

Neural arch of this vertebrae is divisible in 2 parts with a ligament. In the upper part of the ligament,
Spinal cord is present. In lower part odontoid fossa is present in which odontoid process of axis is fitted
to make pivot joint. (Also called as median atlanto axial joint)

On each surface of atlas a pair of articular process are present. The upper pair articulates with condyle
of skull to form Rt & Lt Atlantooccipital joints.

Lower pair articulates with superior Articular process of axis to make Rt & Lt Lateral atlanto axial
joints.

Axis : C2 - Centrum is present. At anterior surface of centrum a long odontoid process is present which
fits into odonotoid fossa of atlas vertebrae.

Only C7 has demifacets where upper part of head of 1st Rib articulates.
Note : Cervical vertebrae are 7 in all mammals is despite of long or small neck.
(II) Thoracic vertebrae



Thoracic vertebrae are present in chest.
They are 12 in number.
Presence of costal demifacets helps in their identification
(III)Lumbar vertebrae



Lumbar vertebrae are present in the abdomen.
They are 5 in number.
Lumbar vertebrae are largest and heaviest.
(IV)Sacral vertebrae


They are 5 in number.
The 5 sacral vertebra fuse to form single bone.
Superior articular
process
Articular surface for
body of last lumbar process
Lateral part of
upper surface
Sacral foramen
Lateral part
Transverse
ridges
Coccyx
Fig.: Sacrum of man
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(V) Coccygeal vertebrae

These are 4 in number.

The 4 vertebrae fuse to form curved and triangular bone, called the coccyx or tail bone.
JOINTS
Study of joints is called Arthrology.
Types of joints
Joints are mainly of 3 types1. Immovable or fibrous joints / Synarthroses
2. Slightly movable or cartilaginous joints / Amphiarthroses.
3. Freely movable or synovial joints/Diarthroses
Articular
cartilage
Suture
Intervertebral
disc
Synarthroses
Joint
capsule
Synovial
(or joint)
cavity
Amphiarthroses
Synovial
membrane
Diarthroses
Structural Classification :
(A) Fibrous joints (Immovable) : Also called as Synarthrosis.
(i) Sutures : Eg. Skull
(ii) Syndesmosis : Bones are connected by interosseus ligament e.g. inferior tibio fibular joints.
(iii) Gomphosis : (Peg & Socket) – e.g. tooth in its socket
(B) Cartilagenous joints (Slightly movable) : also called as amphiarthrosis
(i) Primary : hyaline cartilage joints (synchondrosis). After certain age the cartilage is replaced by bone
e.g. jointbetween Epiphysis & Shaft.
(ii) Secondary : (Symphysis) fibro cartilagenous joints. Articular surface are covered by a thin layer of
hyaline cartilage & united by a disc of fibro cartilage. there joint are persistant throughout life.
e.g. Symphysis pubis, intervertebral joint.
(C) Freely movable or Synovial joint : also called as diarthrosis

The ends of both the bones are covered by hyaline cartilage or articular cartilages.

The cartilage provides smooth and elastic surface and reduce friction and acts as shock absorber.

In between two bones a space is found called synovial space or cavity. This space provides free
movement to the bone.

The synovial cavity is lined by a synovial membrane. Synovial membrane contains secretory cells.
Synovial membrane secrete or fluid called synovial fluid.
Synovial fluid lubricates and nourish the joints.
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Type of Synovial joints : (Most mobile) :
(i) Plain synovial or gliding joint : Permit slight gliding
movement e.g., joint between articular processes of
vetebrae and joints between Carpals.
(ii) Hinge joint : Movements are permitted in one plane
around transverse axis e.g. elbow, ankle, intephalangeal
joint.
Hinge joints
(iii) Pivot joint : Articular surfaces comprise of
- a central bony pivot
- surrounded by osteoligamentous ring
movement are permitted in one plane around vertical
axis. e.g. radioulnar joint, median atlanto axial joint.
Pivot or rotating joints
(iv) Condylar joint : Articular surface include two distinct
condyles and movement are permitted in both transverse
& vertical axis. Rt & left jaw joint.
(v) Ellipsoid joint : e.g. wrist, Metacarpophalengeal joint.
movement are permitted in both axis, but articular
surfaces are not in form of condyles.
Saddle joints (Biaxial joints)
(vi) Saddle joint : Articulating surface are reciprocally
concavo convex. these are improperly developed ball &
socket joints e.g. first carpometacarpal joint and
calcaneocuboid joint.
(vii) Ball & socket joint : Here one articular surface is like
a ball and other of the shape of socket and movements
are possible around infinte axises. e.g. shoulder & Hip
joint.
ROLE OF MUSCLES AND BONES IN MOVEMENT
(i) Movement of an organ occurs due to the pulling of the bones caused by force generated due to
contraction in muscles. Movements take place along the joints which act as fulcrum of the lever.
(ii) Three types of lever functioning can be observed in movements of human joints .
(A) Class I lever : Here Fulcrum is between effort & resistance.
Example : Joint between the first vetebra (ATLAS) and occipital
bone of skull.
Fulcrum : is the joint
Effort : is contraction of back muscles.
Resistance : Weight of the facial bone of skull.
(B) Class II lever : Here resistance is between effort Y fulcrum.
Example : Human body restingh on toe.
Fulcrum : Is the toe
Effort : Is contraction of calf muscle.
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Resistance : Is body Weight.
(C) Class III lever : Here effort is between resistance and fulcrum.
Example : Flexing movement of the elbow of forearm.
Fulcrum : Is the elbow joint.
Effort : Is contraction in Bicep muscle.
Resistance : Weight of distal part of hand.
SKELETAL DISORDER
(i) Dislocation : It is displacement of bone from their normal position at joint.
(ii) Slipped disc : It is displacement of intervertebral fibrocartilage disc or vertebrae from their normal
position.
(iii) Sprain : It is stretching or tearing of tendons or ligaments.
(iv) Osteitis or Osteomyelitis : It is inflammation of bone.
(v) Spondylitis : It is inflammation of one or more vertebrae.
(vi) Osteoporosis : It is excessive loss of calcium and phosphorus from the bone.
(vii) Rickets : In this disease bones of leg get curved bowlegs, It is due to deficiency of vitamin D.
CHARACTERISTICS OF FEMALE'S SKELETON
(i)
(ii)
(iii)
(iv)
(v)
Skull - Female skull is lighter in comparison to male.
Shoulders - Female shoulder's are narrower.
Sacrum - Female sacrum is shorter and wider.
Pelvis - Female pelvis is lighter and broader.
Pelvic cavity - The female cavity is wider in diameter to accommodate the growing foetus during
pregnancy and to facitilate the child birth.
(vi) Coccyx : Female coccyx is more movable than male coccyx.
TYPES OF BONES (ON BASIS OF SHAPE AND SIZE)
(i) Long bones
e.g. Humerus, Radius, Ulna, Tibia fibula, Femur.
(ii) Short bones
e.g. Carpals and tarsals.
(iii) Flat bones
e.g. Skull bone, sternum and ribs.
(iv) Irregular bones
e.g. Ear ossicles and vertebrae.
(v) Sesamoid bones
e.g. Patella (knee cap)., pisciform
SPECIAL POINTS
(i) The bones of a children have large amount of organic matter, so, their bones are very flexible and less
likely to break. (hence they may undergo green stick fracture)
(ii) In frog tibiofibula is the longest bone.
(iii) Bones formed by ossification in cartilages is called replacing bone e.g. Humerus, femur.
(cartilagenous bones)
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(iv) Bones formed by ossification in the dermis and sink to get attached over the cartilages. e.g. Frontals
and parietals is called investing bone of the skull.(Dermal bones or membranous bones)
(v) Bones formed by ossification in the tendons at the joint is called sesamoid bones e.g. Patella.
(vi) Skull of reptiles and birds possess one occipital condyles so the skull is called monocondylic, skull
of amphibians and mammals possess two occipital condyles, so the skull is called dicondylic.
(vii) Os penis : A bone supporting the penis of bats is called os penis.
(viii) Os cordis : A bone supporting the heart of cattle is called oscordis.
(ix) The end of two bones are connected by ligaments. While a muscle atlaches with bone through tendon.
(x) Procoelous - Centrum concave anteriorly but convex posteriorly 2nd to 7th vertebrae of frog. All reptilian
vertebrae are procoelous.
Amphicoelous - Centrum concave on both sides. 8th vertebrae of frog is amphicoelous.
Acoelous - Centrum remain flat. 9th vertebra of frog is acoelous.
Heterocoelous - Centrum partly convex and partly concave on both sides.
Vertebrae of birds are heterocoelous.
Coeloplatyn vertebrae - Centrum concave anteriorly but flat posteriorly.
Platycoelous vertebrae - Centrum flat anteriorly but concave posteriorly.
(xi) In Avian skull sutures remains absent.
(xii) Weberian ossicles - These are modified in vertebrae in cat and fishes. These help in sound production
by connecting air bladder and internal ear.
(xiii) Like mammals amphibian skull is also dicondylic.
Skull of reptiles and aves are monocondylic.
(xiv) The pelvic girdle of birds is attached to a complex structure formed by the fusion of last thoracic all
lumbar and first five caudal vertebra this structure is called synsacrum.
(xv) Talus in Rabbit is called as Astragalus.
(xvi) Weberian ossicles are found in fishes.
(xvii) Fontanelles are temporary apertures present in the skull of a new born baby.
(xviii) Superior and inferjor articular processes of vertebrae are also called as pre and post zygapophysis
respectively.
(xix) In rabbit elbow and knee joints are also called ginglymoid joints.
(xx) Cnenial crest is a ridge found is Tibia of Rabbit.
(xxi) Trochlear notch of Rabbit is also called as sigmoid notch.
(xxii) Zygomatic arch of rabbit is formed of maxilla, squamosal and jugal bone.
(xxiii)
(xxiv)
(xxv)
(xxvi)
(xxvii)
(xxviii)
Pelvic girdles are made of two hip bones which are also called as Innominates.
Dentary is a membranous bone found in the lower jaw of same vertebrates like frog.
Jaw suspension of mammals is craniostylic.
Pterygoid bone is a wing shaped extension of sphenoid bone in Rabbit’s skull.
Movement of hands while walking occurs for balancing.
A small sessamoid bone Fabella often develops in the tendon of lateral haed of gastromenius muscles
behind the knee joint.
DISORDERS OF BONES
1. Arthritis
It is caused by the inflammation of the joints. This of several types, e.g., rheumatoid arthritis, osteoarthritis
and gouty arthritis.
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(A) The Rheumatoid Arthritis
(Rheum = Watery secretion of the body) It is diagnosed by the presence of rheumatoid factor (a type of
immunoglobulin gM).
 It is the primary symptom of inflammation of synovial membrane.
 If it is left untreated, then the membrane thickens and synovial fluid increases, exerting pressure that
causes pain.
 The membrane then starts secreting abnormal granules, called pannus, which after accumulating on
the surface of the cartilage, cause its erosion.
 As a result, the fibrous tissues are attached with the bones and become ossified, making the joints
immovable.
(B) Osteoarthritis
It is a degenerative joint disease characterised by the degeneration of the articular cartilage and
proliferation of new bones. Usually, afflicted joints are of spine, knees and hands.
(C) Gouty Arthritis or Gout
It is caused either due to excessive formation of uric acid, or inability to excrete it. It gets deposited in
joints as monosodium salt.
Treatment – Reduction of pain and inflammation by heat treatment and physiotherapy and, in extreme
cases, replacement of the damaged joints. Traditionaly the toxin of honey bee is also used.
2. Osteoporosis




It is an age-dependent systemic disorder characterised by low bone mass, microarchitectural
deterioration of the bone, increased fragility and proneness or susceptibility to fracture.
The elderly men and women are most susceptible.
It may occur in a pregnant woman, In individuals under prolonged treatment of cortisone, the skeleton
fails to withstand the stress of the body and bones are easily fractured.
Imbalances of hormones like thyrocalcitonin, parathyroid and sex-hormones, deficiencies of calcium
and vitamin D, menopause are the major causative factors.
IMPORTANT POINTS OF FROG SKELETON SYSTEM
(i)
(ii)
(iii)
(iv)
(v)
(vi)
Total number of bones in frog are 150.
Total number of skull bones are 30.
Skull of frog is dicondylic.
In frog, ribs are absent.
In frog, sternum is associated with pectoral girdle.
In frog, pectoral girdle is formed of episternum (cartilage), xiphisternum (cartilage) omosternum (bone),
mesosternum (bone).
(vii) Half of the pelvic girdle of frog is osinnominatum. Each os-innominatum is formed of ilium, pubis and
ischium.
(viii) Forelimb of frog includes humerus, radioulna, carpels, metacarpels and phalanges. Phalanges formula
of hand is 02233.
(ix) Hindlimb of frog includes. Femur, Tibia fibula, Astragalus, calcaneum and bones of foot.
Note :
In frog, largest and longest bone is tibia fibula.
Digital formula for foot in frog is 22343.
Vertebral column of frog is composed of 10 vertebrae 10th vertebrae is called urostyle.
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EXERCISE#1
Q.1
Number of bones in the adult human body is(1) 206
(2) 406
(3) 106
(4) 306
Q.14
The total number of vertebrae in man is(1) 33
(2) 32
(3) 35
(4) 45
Q.2
Comparative study of skulls is(1) Craniology
(2) Conchology
(3) Malacology
(4) Osteology
Q.15
The number of ribs in human body is(1) 10
(2) 12
(3) 24
(4) 36
Q.16
Q.3
Bone formed by ossification in a tendon is
called(1) Membrane bone
(2) Dermal bone
(3) Cartilage bone
(4) Sesamoid bone
The number of 'true ribs' in a man is(1) 12 pair
(2) 7 pair
(3) 3 pair
(4) 2 pair
Q.17
In man, the ribs are attached to(1) Clavicle
(2) Sternum
(3) Scapula
(4) Coracoid
Q.18
Movable joints are called(1) Synovial joints
(2) Fibrous joints
(3) Symphyses
(4) Cartilaginous joint
Q.19
At the articular surface of the bones, synovial
fluid serve to(1) Seal
(2) Lubricate
(3) Keep distance
(4) Join
Q.20
Articulation of ulna with humerus at the
elbow joint is(1) Hinge
(2) Ball and socket
(3) Pivotal
(4) Gliding
Q.21
Pivot joint occurs at(1) The hip and shoulder joints
(2) Between the atlas and the odontoid
process of the axis
(3) Sternoclavicular joints
(4) Temporomandibular joint
Q.22
Synovial fluid is found in (1) Cranial cavity
(2) Spinal cavity
(3) Immovable joints
(4) Freely movable joints
Q.23
Stiffness of joints can be due to the (1) Decrease in synovial fluid
(2) Increase in synovial fluid
(3) Higher viscosity of synovial fluid
(4) None of these
A disease associated with joint is(1) Gloucoma
(2) Arthritis
(3) Paget's disease
(4) Horner's syndrome
Q.4
Extremities of long bones possess(1) Calcified cartilage (2) Fibrous cartilage
(3) Hyaline cartilage
(4) Elastic cartilage
Q.5
Number of bones in human axial skeleton is(1) 120
(2) 142
(3) 80
(4) 206
Q.6
Epiphyseal plates at the extremities of long
bones help in (1) Bone moulding
(2) Elongation of bone
(3) Bone formation
(4) Formation of haversian canals
Q.7
Patella, the knee cap is an example of(1) Cartilaginous bone (2) Sesamoid bone
(3) Membrane bone
(4) Investing bone
Q.8
Human vertebra is an example of(1) Long bone
(2) Flat bone
(3) Seamoid bone
(4) Irregular bone
Q.9
The smallest irregular bone in man is(1) Patella
(2) Stapes
(3) Nasal
(4) Palatine
Q.10
The number of bone in the skull of man is(1) 14
(2) 29
(3) 8
(4) 20
Q.11
Foramen magnum is present at(1) Base of medulla
(2) Base of skull
(3) Apex of vertebral column
(4) Base of brain
Q.12
The only movable bone in the skull is(1) Mandible
(2) Maxilla
(3) Ethmoid
(4) None
Q.13
In man coccygeal bone is formed by the
fusion of(1) 3 vertebrae
(2) 4 vertebrae
(3) 5 vertebrae
(4) 6 vertebrae
Q.24
Q.25
Bone dissolving cells are known as(1) Osteoblasts
(2) Chondroblasts
(3) Osteoclasts
(4) Chondroclasts
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Q.26
Ilium is a bone of-
Q.39
Deltoid ridge of humerus is meant for(1) Articulation
(2) Attachment of muscles
(3) Protection
(4) None of the above
Q.40
Six of the 206 bones of human skeleton
occur in(1) Skull
(2) Middle ear
(3) Pectoral girdle
(4) Pelvic girdle
Q.41
Astragalus and calcaneum occurs in(1) Shoulder
(2) Hip
(3) Fore limb
(4) Hind limb
Long neck of Camel or Giraffe has(1) Numerous cervical vertebrae
(2) Development of extra large intervertebral pads
(3) Longer vertebrae
(4) Development of extra bony plates between
adjacent cervical vertebrae
Q.42
Avian (bird) skull is(1) Monocondylic
(3) Acondylic
Human vertebral formula is known as(1) C4T8L4S8C8
(2) C7T8L5S6C7
(3) C7T12L5S4C5
(4) C7T 12L5S(5)C(4)
Q.43
Number of bones present in hind limb of
human being is(1) 25
(2) 30
(3) 35
(4) 40
Q.44
The number of carpals in each fore arm of
human beings is(1) 5
(2) 6
(3) 7
(4) 8
Q.45
Patella, the knee cap is the example of(1) Cartilage gland
(2) Replacing bone
(3) Sesamoid bone
(4) None of these
(1) Cranium
(3) Pelvic girdle
(2) Pectoral girdle
(4) Fore arm
Q.27
Number of cervical vertebrae in man is (1) 5
(2) 6
(3) 7
(4) 8
Q.28
Clavicle is a bone of(1) Thigh
(3) Knee joint
Q.29
Q.30
Q.31
Q.32
Q.33
(2) Shoulder
(4) Shank
Ankle joint is(1) Pivot joint
(2) Ball and socket joint
(3) Hinge joint
(4) Gliding joint
(2) Dicondylic
(4) None of these
Coronary process is a part of(1) Upper jaw
(2) Lower jaw
(3) Hyoid apparatus
(4) Cranium
Joints between carpals are(1) Fibrous joints
(2) Cartilagenous joints
(3) Angular joints
(4) Gliding joints
Q.34
The only movable bone in the skull is(1) maxilla
(2) Frontoparietal
(3) Mandible
(4) Nasal
Q.46
The joint present in the human neck is(1) Angular
(2) Pivot
(3) Hinge
(4) Fibrous
Q.35
Immovable joints are called(1) Sutures
(2) Amphiarthroses
(3) Diarthroses
(4) None of the above
Q.47
Coccygeal bone is formed by the fusion of
bones in man(1) 3 vertebrae
(2) 6 vertebrae
(3) 5 vertebrae
(4) 4 vertebrae
Q.48
Q.36
Glenoid cavity is found in(1) Humerus
(2) Pectoral girdle
(3) Pelvic girdle
(4) Skull
The central part of long bone is known as(1) Diphysis
(2) Epiphysis
(3) Hypophysis
(4) Zygapophysis
Q.49
Q.37
The first vertebra of vertebrae column of man
is known as(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
In body membrane surrounding the bone is
known as(1) Periosteum
(2) Endo-oesteum
(3) Perichondrium
(4) Chondriocytes
Q.50
The hardest substance in human body is
present in(1) Bone-Ossein
(2) Chitin - Protein
(3) Tooth - Enamel
(4) Muscle - Myosin
Q.38
The number of pairs of true ribs in man is (1) 6
(2) 7
(3) 9
(4) 10
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Joints are lubricated by(1) Epidermis
(2) Dermis
(3) Tympanic membrane
(4) Synovial fluid
Q.62
Q.63
Number of bones found on face are(1) 14
(2) 18
(3) 28
(4) 16
Q.52
In mammals , the largest vertebra is(1) Cervical
(2) Lumbar
(3) Caudal
(4) Sacral
Q.64
Number of floating ribs in man is(1) 7 pairs
(2) 3 pairs
(3) 1 pair
(4) 2 pairs
Q.53
Interphalangial joints are also called as(1) Fixed joints
(2) Hinge joints
(3) Movable joints
(4) Straight joints
Q.65
Tongue bone is(1) Sensory capsule
(3) Manubrium
Presence of furcula is a characteristics feature
of (1) Frogs
(2) Reptiles
(3) Birds
(4) Mammals
Q.66
Number of thoracic vertebrae in man is(1) 5
(2) 7
(3) 4
(4) 12
Q.67
Number of vertebrae in rabbit is(1) 40-44
(2) 42-48
(3) 44-47
(4) 47-50
Q.68
Digital formula of both limbs in man(1) 2, 3, 3, 4, 3
(2) 2, 3, 3, 3, 3
(3) 3, 3, 3, 3, 2
(4) 2, 2, 3, 3, 3
Q.69
Which of the following is not a sesamoid
bone(1) Patella
(2) Fabella
(3) Radius
(4) Pisciform
Q.70
Which of the following is a flat bone(1) Tibia
(2) Tarsal
(3) Malleus
(4) Sternum
Q.71
Articular cartilage of synovial joint is(1) Fibrocartilage
(2) Hyaline cartilage
(3) Elastic cartilage
(4) All of these
Q.51
Q.54
Q.55
Q.56
Q.57
Q.58
Q.59
Q.60
Q.61
Obturator foramen in pelvic girdle of mammals
is formed by(1) Pubis and ischium
(2) Pubis and ilium
(3) Ilium and ischium
(4) Ilium, ischium and pubis
When joint becomes inflamed and painful,
condition is not called(1) Rheumatism
(2) Sprain
(3) Osteoarthritis
(4) Gouty arthritis
In the ball and socket joint the friction of two
bones is lessened by(1) Pericardial fluid
(2) Pleural fluid
(3) Synovial fluid
(4) Coelomic fluid
Skull is formed of(1) 58 bones
(3) 29 bones
(2) 28 bones
(4) None
(2) Hyoid bone
(4) Palatine
Q.72
Twelve pairs of ribs and twelve pairs of cranial
nerves are found in(1) Fish
(2) Frog
(3) Lizard
(4) Man
Which of the following joint is found between
carpals and radius(1) Ellipsoid
(2) Pivotal
(3) Hinge
(4) Gliding
Q.73
Incus is modified(1) Parietal bone
(3) Quadrate bone
Joint of femur with pelvic girdle is(1) Ball and socket
(2) Pivotal
(3) Saddle
(4) Hinge
Q.74
Immovable joint is(1) Synarthrodial
(3) Diarthrodial
(2) Jugal bone
(4) Premaxilla bone
Heaviest vertebra in man is(1) Atlas
(2) Axis
(3) Thoracic
(4) Lumbar
Beak, feathers, nails are(1) Exoskeleton
(2) Endoskeleton
(3) Epidermal exoskeleton
(4) Dermal exoskeleton
Q.75
(2) Amphiarthrodial
(4) All of these
Old people are, more liable to fracture of their
bones because(1) Bones become soft and elastic
(2) Bone Calcium decreases
(3) Bones contain large quantity of organic
magnesium
(4) None of the above
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Q.76
Inflammation of one or more vertebrae is called(1) Osteitis
(2) Osteoporosis
(3) Spondylitis
(4) Dislocation
Q.77
Os-cordis a bone in(1) Whale
(3) Cattle
Q.78
(2) Bats
(4) Polar bear
Which of the following is false regarding
synovial fluid(1) It is secreted by synovial membrane
(2) Its deficiency leads to osteoporosis
(3) It lubricates joints
(4) It nourishes the structure participating in
joint
Q.79
Which one is bone of fore limb [CPMT 1991]
(1) Humerus
(2) Femur
(3) Tibia
(4) Fibula
Q.80
A cup shaped cavity for articulation of femur
head is [CPMT 1983]
(1) Acetabulum
(2) Glenoid cavity
(3) Sigmoid notch
(4) Obturator foramen
Q.81
Number of bones present in human cranium is[BHU 1985]
(1) 8
(2) 10
(3) 12
(4) 16
Q.82
Number of bones present in forelimb of human
[CPMT 1974, 1976]
(1) 30
(2) 32
(3) 35
(4) 40
Q.83
Patellar groove is found on which bone [CPMT 1972]
(1) Femur
(2) Tibio-fibula
(3) Depression between femur and tibio-fibula
(4) Tarsus
Q.86
Ribs are attached to [CPMT 1983, RPMT 1996, ardha 2001]
(1) Scapula
(2) Sternum
(3) Calvicle
(4) llium
Q.87
Vertebro-arterial canal occurs in [MPPMT 1990]
(1) Cervical vertebrae (2) Lumbar vertebae
(3) Thoracis vertrae
(4) sacral vertebrae
Q.88
Which vetebra hat hte odontoid process [CPMT 1990]
(1) 7th vertebra of Frog
(2) Second vertebra of Frog
(3) Second cervical vertebra of mammal
(4) Second thoracic vertebra of mammal
Q.89
In human beings, the second cervical vertebra
helps in rotatory movements of head through
knob-like process called [CPMT 1987]
(1) Prezygapohysis
(2) ostzygapolysis
(3) Postzyapohysis
(4) Odontoid process
Q.90
Pectoral girdle, pelvic girdle and limb bones
constitude [CPMT 1987]
(1) Visceral skeleton
(2) Outer skeleton
(3) Axial skeleton
(4) Appendicular skeleton
Q.91
Joint between bones of human skull is [CBSE 1994]
(1) Hinge joint
(2) Synovial joint
(3) Cartilaginous joint (4) fibrous joint
Q.92
Acromion process is part of MPPMT 1994, 1995]
(1) Vertebral column
(2) Pelvic girdle
(3) Femur
(4) Pectoral girdle
Q.84
Greater trochanter occures in [CPMT 1981]
(1) Humerus
(2) Radius
(3) Ulna
(4) Femur
Q.93
Head of humerus is articulate with pectoral
girdle by a joint [CPMT 1996]
(1) Hinge
(2) Ball and socket
(3) Immovable
(4) Pivot joint
Q.85
Sella turcica is [BHU 1976,AIIMS 2001, Wardha 2001]
(1) Depression of long bone
(2) Ridgee over a bone
(3) epression in the skull in the area of putuitary
gland
(4) Rdige in the skull over the area of pituitary
gland
Q.94
Sesamoid bone is derived from [CPMT 1996]
(1) Cartilage
(2) Areolar tissue
(3) Tendon
(4) Ligament
Q.95
Surface for attachment of tongue is [CBSE 1997]
(1) Palatine
(2) Sphenoid
(3) Pterygiod
(4) Hyoid apparatus
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Q.96
Inter-articular disc occcurs in (1) Wall of heart
(3) Pubic symphysis
Q.97
[BHU 1997]
(2) Wall of liver
(4) Hyoid apparatus
Pelvic girdle consists of [RPMT 1998]
(1) llium
(2) llium and ischium
(3) llium, ischium and pubic
(4) Ischium and pubis
Q.98
Coracoid is component of (1) Fore limb
(3) Scapula
Q.99
[BHU 1999]
(2) Skull
(4) Pelvic girdle
Olecranon process occurs in [BHU 1999, Manipal 2001]
(1) Femur
(2) Radius
(3) Humerus
(4) Ulna
Q.100 Sutrual joints are present between [MPMT 2000]
(1) Thumb and metatarsal
(2) Humerus and radio-ulna
(3) Parietals of skull
(4) Glenoid cavity and pectoral girdle
Q.101 Coccygeal bone occurs in (1) Skull
(3) Vertebral column
[CPMT 2000]
(2) Pectoral girdle
(4) Pelvic girdle
Q.102 Synovial fluid is present in [Har. PMT 2000]
(1) Spinal cavity
(2) Cranial cavity
(3) Freely movable joint (4) Fixed joints
Q.103 Zygomatic is part of (1) Pelvic girdle
(2) Skull
(3) Pectoral girdle
(4) Vertebral column
Q.107 Bone related with skull of rabbit is [CBSE 2000]
(1) Coracoid
(2) Arytenoid
(3) Pterygoid
(4) Atlas
Q.108 An acromian process is characteristically
found in the [CBSE 2005]
(1) Pectoral girdle of mammals
(2) Sperm of mammals
(3) Pelvin girdle of mammals
(4) Skull of frog
Q.109 Which of the following pairs, is correctly
matched ?
[CBSE 2005]
(1) Fibrous joint - between phalanges
(2) Cartilaginous joint - Skull bones
(3) Gliding joint - between zygapophyses of
the successive vertebrae
(4) Hinge joint - between vertebrae
Q.110
[B.V. 2001]
(2) Cartilage
(4) synovial membrane
Q.105 llium of pelvic girdle is articulate with sacrum
for [B.V 2001]
(1) Bending
(2) Jumping
(3) Support
(4) Running
In human body, which one of the following is
anatiomically correct ?
[CBSE 2007]
(1) Cranial nerve - 10 pairs
(2) Floating ribs - 2 pairs
(3) Collar bones - 3 pairs
(4) Salivary glands - 1 pair
Q.111
[B.V. 2000]
Q.104 Synovial fluid is secreted by (1) Blood
(3) Bone
Q.106 Which one is a ball and socket joint [Wardha 2001]
(1) Knee joint
(2) Elbow joint
(3) Humerus and pectoral girdle
(4) skull and atlas
(1)
(2)
(3)
(4)
Three of the following pairs of the human skeletal parts are correctly matched with their respective inclusive skeletal category and one pair
is not matched. Identify the non-matching pair.
[AIPMT MAINS 2011]
Pairs of skeletal parts
Category
Malleus and stapes
Ear ossicles
Sternum and Ribs
Axial skeleton
Clavicle and Glenoid cavity Pelvic girdle
Humerus and ulna
Appendicular
skeleton
Q.112
The joint of Radio-ulna with the upper arm is
[RPMT 2011]
(1) hinge joint
(2) pivot joint
(3) socket joint
(4) None of these
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STATE PMT EXAMS EXERCISE#2
Q.1
the joint of radio-ulna with upper arm is [Uttaranchal PMT 2005]
(1) Hinge joint
(2) Gliding joint
(3) Socket joint
(4) Pivot joint
Q.2
Obturator foramen is found in [UP CPMT 2001]
(1) Frog’s pelbic girdle
(2) Frog’s pectoral girdle
(3) Rabbit pelbic girdle
(4) Rabbit’s pectoral girdle
Q.3
Deltoid ridge is present in [UP CPMT 2004]
(1) Humerus
(2) Tibia-fibula
(3) Radio-ulna
(4) Femur
Q.4
Pelvic girdle of rabbit consists of [UP CPMT 2004]
(1) llium, ischium and pubis
(2) llium, ischium and coracoid
(3) Coracoid, scapula and clavicle
(4) llium, coracoid and scapula
Q.5
Q.6
Structure responsible for formation fo signoid
notch is [UP CPMT 2005]
(1) Olecranon process of humerus
(2) Olecranon process of femur
(3) Olecranon process of radius ulna
(4) Olecranon process of tibia fibula
Lumbar vertebrae are found in [UP CPMT 2005]
(1) Neck region
(2) Abdominal region
(3) Hip region
(4) Thorax
Q.7
Innominate is [UP CPMT 2006]
(1) A nerve and an artery
(2) A nerve and a vein
(3) A vein and an artery
(4) A part of skeleton and an artery
Q.8
Sigmoid notch in Rabbit is present in [UP CPMT 2006]
(1) Radius ulna
(2) Tibia
(3) Humerus
(4) Femur
Q.9
Number of bones in skull is [MP PMT 2007]
(1) 26
(2) 18
(3) 107
(4) 29
Q.10
Hinge joint is present between [MP PMT 2007]
(1) Femur and ulna
(2) Humerus and ulna
(3) Femur and pectoral girdle
(4) Femur and pelvic girdle
Q.11
Thoracic cage in rabbit is made up of [UP PMT 2006]
(1) Ribs, vertebral column and diaphragm
(2) Ribs, diaphgragm
(3) Vertebral column, diappragm and sternum
(4) Ribs, vertebral column and sternum
Q.12
In which one of the following bones acromian
process is found [MP PMT 2005]
(1) Femur
(2) Pelvic girdle
(3) Atlas
(4) Pectoral girdle
Q.13
The joint formed between humerus and radio
ulna is [MP PMT 2006]
(1) Gliding
(2) Pivot
(3) Hinge
(4) Ball and socket
Q.14
Fabellae bones are associated with
[MP PMT 2002]
(1) Elbow joint
(2) Knee joint
(3) Neck joint
(4) Angular joint
Q.15
Thoracic cage of man is formed of [MP PMT 2002]
(1) Ribs and thoracic vertebrae
(2) Ribs, sternum and thoracic vertebrae
(3) Ribs and sternum
(4) Ribs, sternum and Lumbar vertebrae
Q.16
Jaw suspension characteristic of mammals is
[MP PMT 2002]
(1) Amphistylic
(2) Craniostylic
(3) Autodiastylic
(4) Hyostylic
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ANSWER KEY
EXERCISE # 1
Ques.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Ans.
1
1
4
3
3
2
2
4
2
2
2
1
2
1
3
2
2
1
2
1
Ques.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Ans.
2
4
1
2
3
3
3
2
3
4
1
2
4
3
1
2
1
2
2
2
Ques.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Ans.
3
4
2
4
3
2
4
1
1
3
4
2
2
3
1
2
3
4
3
4
Ques.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Ans.
3
3
1
4
2
4
3
2
3
4
2
1
1
1
2
3
3
2
1
1
Ques.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Ans.
1
1
1
4
3
2
1
3
4
4
4
4
2
3
4
3
3
3
4
3
Ques. 101 102 103 104 105 106 107 108 109 110 111 112
Ans.
3
3
2
4
3
3
3
1
3
2
3
1
STATE PMT EXAMS EXERCISE # 2
Que s.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Ans.
1
3
1
1
3
2
4
1
4
2
4
4
3
2
2
2
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