Download Chapter 7 - The Axial Skeleton

Biol 2401
Fundamentals of Anatomy and Physiology
Mrs. Willie Grant
[email protected]
(210) 486-2780
© 2012 Pearson Education, Inc.
Chapter 7
The Axial Skeleton
Lecture Presentation by
Lee Ann Frederick
University of Texas at Arlington
© 2015 Pearson Education Inc.
© 2012 Pearson Education, Inc.
An Introduction to the Axial Skeleton
Learning Outcomes
7-1 Identify the bones of the axial skeleton, and specify their functions.
7-2 Identify the bones of the cranium and face, and explain the
significance of the markings on the individual bones.
7-3 Identify the foramina and fissures of the skull, and cite the major
structures using the passageways.
7-4 Describe the structure and functions of the orbital complex, nasal
complex, and paranasal sinuses.
7-5 Describe the key structural differences among the skulls of infants,
children, and adults.
7-6 Identify and describe the curvatures of the spinal column, and indicate
the function of each.
7-7 Identify the vertebral regions, and describe the distinctive structural
and functional characteristics of vertebrae in each region.
7-8 Explain the significance of the articulations between the thoracic
vertebrae and the ribs, and between the ribs and sternum.
© 2012 Pearson Education, Inc.
© 2012 Pearson Education, Inc.
© 2012 Pearson Education, Inc.
7-3 The Cranial Bones of the Skull
Sinuses
Cavities that decrease the weight of the skull
Lined with mucous membranes
Protect the entrances of the respiratory system
Auditory Ossicles
Three tiny ear bones in the middle ear that connect the tympanic membrane with one of
the receptor complexes of the internal ear.
Malleus
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Anvil
Stapes
7-4 The Orbital and Nasal Complexes
The Eye Sockets (Orbits)
Frontal bone (roof)
Maxilla (floor)
Maxillary, lacrimal, and ethmoid bones (orbital rim and medial wall)
Sphenoid and palatine bones
2 Which seven bones for the orbit?
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7-4 The Orbital and Nasal Complexes
Bones of the Nasal Cavities and Paranasal Sinuses Make Up the Nasal
Complex
Frontal bone, sphenoid, and ethmoid
Superior wall of nasal cavities
Maxillae, lacrimal bones, ethmoid, and inferior nasal conchae
Lateral walls of nasal cavities
Maxillae and nasal bones
Bridge of nose
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Figure 7-14a The Nasal Complex
FRONTAL BONE
Frontal sinuses
ETHMOID
NASAL BONE
PALATINE BONE
(bony palate)
MAXILLA
(bony palate)
Sphenoidal
sinuses
SPHENOID
Superior
Middle
INFERIOR
NASAL
CONCHA
A sagittal section through the skull,
with the nasal septum removed to
show major features of the wall of
the right nasal cavity. The
sphenoidal sinuses are visible.
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Nasal
conchae
of ethmoid
7-4 The Orbital and Nasal Complexes
Paranasal Sinuses
Air-filled chambers connected to the nasal cavities
Lighten skull bones
Provide mucous epithelium (flushes nasal cavities)
3 What are the functions of the paranasal sinuses?
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© 2012 Pearson Education, Inc.
7-5 Fontanelles
The Infant Skull
Grows rapidly
Is large compared to the body
Has many ossification centers
Fusion is not complete at birth
Two frontal bones
Four occipital bones
Several sphenoidal and temporal elements
Fontanelles
Are areas of fibrous connective tissue (soft spots)
Cover unfused sutures in the infant skull
Allow the skull to flex during birth
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4 Which fontanel is bordered by four different skull bones?
5 Which fontanel is considered the “soft spot”?
6 How long does it persit?
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7-6 The Vertebral Column
The Vertebral Column (Spine)
Protects the spinal cord
Supports the head and body
26 bones
24 vertebrae, the sacrum, and the coccyx
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Figure 7-16 The Vertebral Column
Spinal Curves
Vertebral Regions
Primary curves develop
before birth, and secondary
curves after birth.
Regions are defined
by anatomical
characteristics of
individual vertebrae.
The cervical curve, a
secondary curve, develops as
the infant learns to balance the
weight of the head on the
vertebrae of the neck.
The thoracic curve, a
primary curve,
accommodates the
thoracic organs.
The lumbar curve, a
secondary curve, balances
the weight of the trunk over
the lower limbs; it develops
with the ability to stand.
The sacral curve, a
primary curve,
accommodates the
abdominopelvic organs.
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Cervical
(7 vertebrae)
Thoracic
(12 vertebrae)
Lumbar
(5 vertebrae)
Sacral
Coccygeal
7 Which curves of the adult
vertebral column are concave
relative to the anterior side of th
body?
“Hunchback”
Exagerrated normal thoracic curve
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“Swayback”
Bending backwards
“Crookedness”
Lateral curvature
7-7 Vertebral Regions
The Cervical Vertebrae
Vertebra prominens (C7)
Transitions to thoracic vertebrae
Has a long spinous process
Has large transverse processes
Ligamentum nuchae (elastic ligament) extends from C7 to skull
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7-8 The Thoracic Cage
Ribs 1–7 (True Ribs)
Vertebrosternal ribs
Connected to the sternum by costal cartilages
Ribs 8–12 (False Ribs)
Do not attach directly to the sternum
Vertebrochondral ribs (ribs 8–10)
Fuse together
Merge with cartilage before reaching the sternum
Floating or vertebral ribs (ribs 11–12)
Connect only to the vertebrae and back muscles
Have no connection with the sternum
8 With which ribs does the body of the sternum articulate?
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© 2012 Pearson Education, Inc.
Clinical Case—Knocked Out
What are the seven bones that make up the orbital complex?
What are the four paranasal sinuses surrounding the orbital complex?
© 2012 Pearson Education, Inc.
© 2012 Pearson Education, Inc.
Chapter 8
The Appendicular
Skeleton
Lecture Presentation by
Lee Ann Frederick
University of Texas at Arlington
© 2015 Pearson Education, Inc.
© 2012 Pearson Education, Inc.
An Introduction to the Appendicular Skeleton
Learning Outcomes
8-1 Identify the bones that form the pectoral girdle, their functions, and
their superficial features.
8-2 Identify the bones of the upper limbs, their functions, and their
superficial features.
8-3 Identify the bones that form the pelvic girdle, their functions, and their
superficial features.
8-4 Identify the bones of the lower limbs, their functions, and their
superficial features.
8-5 Summarize sex differences and age-related changes in the human
skeleton.
© 2012 Pearson Education, Inc.
© 2012 Pearson Education, Inc.
8-1 The Pectoral Girdle
The Pectoral Girdle
Also called shoulder girdle
Connects the arms to the body
Positions the shoulders
Provides a base for arm movement
Consists of:
Two clavicles
Two scapulae
Connects with the axial skeleton only at the manubrium
9 What is the function of the pectoral girdle?
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8-3 The Pelvic Girdle
The Pelvic Girdle
Made up of two hip bones (coxal bones)
Strong to bear body weight, stress of movement
Part of the pelvis
Coxal bones
Made up of three fused bones
Ilium (articulates with sacrum)
Ischium
Pubis
10 What is the function of the pelvic girdle?
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8-3 The Pelvic Girdle
Comparing the Male Pelvis and Female Pelvis
Female pelvis
Smoother and lighter
Less prominent muscle and ligament attachments
Pelvis modifications for childbearing
Enlarged pelvic outlet
Broad pubic angle (>100°)
Less curvature of sacrum and coccyx
Wide, circular pelvic inlet
Broad, low pelvis
Ilia project laterally, not upwards
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Figure 8-10 Anatomical Differences between a Male and Female Pelvis
Ischial
spine
Ischial
spine
90°
or less
Male
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100°
or more
Female
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8-4 The Lower Limbs
Arches of the Feet
Arches transfer weight from one part of the foot to another
The longitudinal arch
Calcaneal portion
Lateral
Talar portion
Medial
The transverse arch
Formed by a difference in curvature between medial and lateral
borders of the foot
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© 2012 Pearson Education, Inc.
8-5 Individual Skeleton Variation
Studying the Skeleton
Reveals characteristics
Muscle strength and mass (bone ridges, bone mass)
Medical history (condition of teeth, healed fractures)
Sex and age (bone measurements and fusion)
Body size
© 2012 Pearson Education, Inc.
© 2012 Pearson Education, Inc.
Clinical Case—The Orthopedic Surgeon’s Nightmare
What skeletal structures are still attached to the distal humeral fracture fragment?
Why would the surgeon want to avoid a circular cast in the immediate post-fracture period and
apply a posterior splint instead?
© 2012 Pearson Education, Inc.