Chapter 7 Key Terms
Atlas
Clavicle
Lamella
Ossification
Red Bone Marrow
Yellow Bone Marrow
Osteoblast
Endosteum
Tubercle
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Axis
Lacunae
Ligaments
Suture
Foramen
Tendon
Osteoclast
Periosteum
Trabeculae
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ANATOMY & PHYSIOLOGY
CHAPTER 7: SKELETAL SYSTEM
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Introduction

Leonardo da Vinci was the first to correctly illustrate the
human skeleton with all 206 bones
 Over

half are found in the foot and hand
Parts of the skeletal system:
 Bones
 Joints
 Cartilage
 Ligaments
 Tendons
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Functions

Supports surrounding tissues

Protects vital organs and soft tissues of the body

Assists in movement

Manufactures blood cells
 Hematopoiesis:

process of making blood
Stores mineral salts
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How is bone made?

Ossification
 The

formation of bone by osteoblasts
Intramembranous Ossification
 Connective
tissue membranes are replaced by deposits of
inorganic calcium salts

Endochondral Ossification
 Organic
matrix synthesized and osteoblast gets surrounded by
bone matrix
 Occurs
everywhere except bones in the skull
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Bone Structure
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Classifications of Bone

Long Bones
 Bones
whose length exceeds their width
 Consist of a diaphysis, metaphysis, epiphyseal line, epiphysis
 Thickness of compact bone is greatest near the middle of the
shaft
 Medullary cavity is found inside the shaft
 Epiphysis is composed mainly of cancellous bone
 Large epiphyses provide large surface area for muscle
attachment and articulation with other bones
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Classifications of Bone

Short bones
 Somewhat
 Lack
irregular in shape
a long axis
 Majority
is cancellous bone surrounded by thin layer of
compact bone
 Carpals
and tarsals
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Classifications of Bone

Flat Bones
 Provide
body
large surface area and protection for vital parts of the
 Consist
of two flat plates of compact bone surrounding
cancellous bone
 Sternum,
ribs, scapula, skull…
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Classifications of Bone

Irregular
 Very
irregular in shape
 Spongy bone enclosed by thin layers of compact bone
 Vertebra and ossicles in ear

Sesamoid
 Small
rounded bones
 Enclosed in tendons and fascial tissue and assist muscle
function
 Patella
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Bone Markings

Processes: any bony prominence or projection
 Spine:
any sharp, slender projection
 Condyle:
rounded prominence usually found at
point of articulation
 Trochanter:
large projection, usually sticking out
of end of bone
 Crest:
narrow ridge of bone
 Neck:
connects head to rest of bone
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Bone Markings

Fossae: any depression or cavity on a bone
 Suture:
narrow junction between two bones
 Foramen:
opening through which blood vessels,
nerves and ligaments pass
 Sinus:
cavity within bone
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Divisions of the Skeleton

Axial Skeleton
 80
bones
 Skull,

hyoid, vertebrae, ribs, sternum
Appendicular Skeleton
 126
bones
 Arms,
clavicle, scapula, legs, pelvic girdle
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Axial Skeleton

Skull (28 bones)
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Axial Skeleton

Hyoid Bone
 Has
no articulations with other
bones
 Supports
the tongue
 Held
by two styloid ligaments
connecting to styloid process
 Helps
elevate larynx (voice box)
during swallowing and speaking
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Axial Skeleton

Vertebrae and
intervertebral disks
 Protect
the spinal cord
 Vertebrae
provide
support for the body
while disks allow for
flexibility
 26
vertebral bones
separated by
intervertebral disks
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Axial Skeleton
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Axial Skeleton

Thorax (25 bones)
 Sternum,
ribs
costal cartilages,

12 pairs of ribs

True Ribs: 1-7

False Ribs 8-10

Floating Ribs: 11-12
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Appendicular Skeleton

Clavicle
 AKA
collar bone
 Connects
to the sternum and scapula
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Appendicular Skeleton

Scapula
 AKA
shoulder blade
 Connects
 Also
the clavicle and humerus
believed to have a part in
movement of the arm
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Appendicular Skeleton

Bones of the arm
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Hand
25
Pelvis
26
Leg
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Foot