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C h a p t e r
42
ithout the skeletal system, movement in the exter-
nal environment would not be possible. The bones
of the skeletal system serve as a framework for skeletal
muscle attachment and movement; protect and maintain
vital structures in their proper position, provide stability
for the body, and maintain the body’s shape. The skeletal
system also serves as a reservoir for ions such as calcium,
phosphorous, and magnesium, and it houses the hemato-
poietic connective tissue in which blood cells are formed.
Structures of the Skeletal
System
The skeletal system can be divided into two functional
parts—the axial and appendicular skeletons (Fig. 42-1).
The
axial skeleton
, which is composed of the bones
of the skull, thorax, and vertebral column, forms the
axis of the body. The
appendicular skeleton
consists of
the bones of the upper and lower extremities, includ-
ing those of the shoulder and hip girdles. In addition to
bones, the skeletal system includes cartilage and liga-
ments that join bones together at joints, giving the body
flexibility and allowing movement to occur.
Two types of connective tissue are found in the skel-
etal system:
cartilage
and
bone
. They both have living
cells that secrete the extracellular matrix in which their
cells are housed. The extracellular matrix in cartilage is
firm but also somewhat pliable, providing the resilience
needed for cushioning of bony structures. In contrast
Structure and
Function of the
Skeletal System
Structures of the Skeletal System
Cartilage
Types of Cartilage
Repair of Hyaline Cartilage
Bones and Bone Structure
Classification of Bones
Parts of a Long Bone
Bone Tissue
Blood Supply
Bone Cells
Bone Formation, Growth, and Remodeling
Bone Growth in Childhood
Bone Remodeling
Hormonal Control of Bone Formation and
Metabolism
Joints
Fibrous Joints (Synarthroses)
Cartilaginous Joints (Amphiarthoses)
Synovial Joints (Diarthroses)
Ligaments and Tendons
Joint Vasculature and Innervation
Bursae and Tendon Sheaths
W
Musculoskeletal
Function
12
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