Download CH 6 skeletal

THE SKELETAL
SYSTEM
CH. 6
INTRODUCTION TO CHAPTER
ROOTS:
 arthr/o = joint
 cervic/o = neck
 chondr/i, chondr/o, chondr/io = cartilage
 cost/o = rib
 myel/o= bone marrow
 occipit/o = back of head
 oss/eo, oss/i, ost/e, ost/eo = bone
 sacr/o = sacrum
 spondyl/o = vertebra
 stern/o = sternum
WHY DO WE NEED A SKELETON?
 It provides a framework for the body and gives it ___________.
 It supports organs and ____________ them from injury.
 It provides a place for muscles, ligaments, and tendons of the
body to ____________ to.
 It helps to make ________________ possible.
 It stores ______________.
 It provides a place for __________________.
WHAT IS BONE AND WHAT IS IT MADE OF?
 Bone is one of the types of ______________ tissue in the
body.
 It is also called _____________ tissue.
 It is made up of water and mineral salts.
 ________________ is the formation of or conversion into
bone or a bony substance (calcification is the deposition of
calcium in a tissue).
WHAT IS BONE MADE OF?
 The outer surface is called _____________ BONE and is very
dense.
 It is the thickest in the midshaft of a long bone to provide
strength and prevent bending of the bone
 The inner layer is called ________________ BONE and is
spongy and latticelike and is less dense than compact bone
WHAT IS BONE MADE OF?
 The SHAFT (____________) of the
bone contains the _____________
CAVITY

It is filled with YELLOW MARROW (fat
storage) and RED MARROW
(hematopoietic tissue)

Yellow marrow replaces red marrow
as an animal ages.
WHAT IS BONE MADE OF?
 ________________ covers the surface of bone and is a
tough, vascular membrane. It is where tendons,
ligaments, and muscles attach to the body. It has a nerve
and blood supply.
 The inner layer of the periosteum contains
___________________ which are cells responsible for
bone growth and repair.
WHAT IS BONE MADE OF ?
 The medullary cavity of bone
has arteries and veins that
enter and exit the cavity
via the ___________
____________ which are
openings in the bone
HOW DO BONES GROW?
 They grow in LENGTH at the junction of the EPIPHYSIS
and the DIAPHYSIS at the _____________ _________
(growth plate). It is also called the ___________.
 They grow in THICKNESS in the layers of the
periosteum.
HOW DO BONES GROW?
 Bones are stimulated to grow via
___________ HORMONE (GH)
which is produced by the
____________ gland.
 There is a teamwork between
______________ producing bony
tissue and _______________
eating away bony tissue to
prevent the bone from becoming
too thick. This process slows as an
animal ages.
SHAPES OF BONE
 ________ (femur, humerus)
 ________ (carpal bones)
 ________ (sternum, scapula)
 ____________ (vertebrae)
AXIAL & APPENDICULAR
SKELETON
 AXIAL SKELETON: SKULL,
HYOID BONE,VERTEBRAL
COLUMN, RIBS, STERNUM
 APPENDICULAR SKELETON:
BONES OF THE LIMBS
SKULL
 2 major segments:

Bones of the Cranium and Facial Bones
 PURPOSE: protects the brain and the sensory organs.
 The ONLY mobile bone is the ______________________
(lower jaw)
 The skull bones unite at the ____________.
•
SINUSES are located within
the skull and are _______filled cavities
•
Sinuses are usually
named for the skull bone
that contains the sinus
The nares open into 2 major air passages that
end in the pharynx. The nasal passages are
filled with very fine scrolls of bone called
___________________.
These are covered in pink mucosa. Air is
warmed, moistened, and filtered as it passes
through the turbinates in the nose on the
way to the lungs.
 CRANIAL BONES

FRONTAL BONES – form the forehead
 Horns are an extension of the frontal bone

PARIETAL BONES – form upper part of each side of the
skull

TEMPORAL BONES – form the lower part of the sides of
the skull.

OCCIPITAL BONE – forms the back of the skull
 foramen magnum– opening at the base of the occipital
bone that allows the spinal cord to pass from the skull
to the spine
 FACIAL BONES

MAXILLA – bone that forms the upper jaw

MANDIBLE – forms the lower jaw. Only
movable bone in the skull
maxilla
mandible

HYOID APPARATUS – U shaped structure made
up of both bone and cartilage. Suspends the
tongue, larynx, and floor of the mouth
VERTEBRAL COLUMN (backbone)
 There are 5 types of vertebrae: ____________(C),
____________ (T), ______________ (L),
____________ (S), _______________ (Cy)

Each vertebrae has a body
and an arch.
– Body – bears the weight
– Arch – forms the canal that
houses the spinal cord
• Intervertebral discs are
between the bodies
• -Made of cartilage and
serve as shock
absorbers
CERVICAL
VERTEBRAE
 1st
vertebrae: _______:
supports the skull
 2nd vertebrae: _____:
what the atlas rotates on
THORACIC VERTEBRAE
 Attach to ribs
 Thoracic Cage: composed
of the thoracic vertebrae,
ribs, costal cartilages,
and sternum

protects the vital organs
of the chest and allows
the lungs to expand and
contract during
respiration
RIBS

PURPOSE: form the thoracic
wall and protect the heart and
lungs

Flat, curved
Each rib has bony and
cartilagenous components
 The cartilagenous
component is located
ventrally
 They unite at the
___________________
junction

STERNUM
 BREASTBONE
 Located on ventral midline of chest
 Flat bones called STERNEBRAE
that connect to each other via
cartilage
 Most cranial bone is the
__________________
 Most caudal bone is the
__________________
LUMBAR VERTEBRAE
 Support the abdomen
SACRAL VERTEBRAE
 One bone that results from the
fusion of 3-5 vertebrae
 Attaches to pelvis
COCCYGEAL VERTEBRAE

Also called caudal or tail vertebrae

Can be docked- spinal cord ends near the
lumbosacral junction
AXIAL & APPENDICULAR
SKELETON
 AXIAL SKELETON: SKULL,
HYOID BONE,VERTEBRAL
COLUMN, RIBS, STERNUM
 APPENDICULAR SKELETON:
BONES OF THE LIMBS
 SCAPULA (shoulder blade)

Large triangular bone on the side
of the thorax
 HUMERUS (upper arm)
 ULNA and RADIUS (forearm)

Ulna forms the elbow
 CARPUS (wrist)

Numerous short/irregular
bones arranged in 2 rows
 METACARPALS (palm)


Vary in number between species (Ex: dog – 5, horse – 3)
Numbered from medial to lateral
 DIGITS (toes)
 Numbered from medial to lateral
 PHALANGES are located within the digits
 Usually 3 phalanges in one digit (P1, P2, P3)
 PELVIS (hip)
 3 pairs of bones that fuse to
become one

IIium – the largest bone



Flares out to the side
Ischium – strongest, most
caudal
Pubis – Most ventral
 FEMUR (thigh)
 Longest bone in the body
 Forms part of the STIFLE
(knee)
 PATELLA (kneecap)
 TIBIA (shin) AND FIBULA
 Tibia is larger than fibula, and
bears more weight
 TARSUS (ankle)
 Called HOCK in animals
 Composed of numerous irregularly
shaped bones arranged in rows
 METATARSALS (foot)



Very similar to metacarpals
Vary in number between species
Numbered medial to lateral
 DIGITS (toes)

Same as forelimb
JOINTS-an articulation between bones and cartilage
that is held in place by ligaments

SYNARTHROSES (Fibrous joints)



AMPHIARTHROSES (Cartilaginous
joints)



no movement
Ex: Skull
slight movement
Ex: Pelvis at pubic symphysis, vertebral column
DIARTHROSES (Synovial joints)



freely movable
Most numerous in the body
Ex: Hip joint, shoulder joint