T
he word
skeleton
comes from the Greek word meaning “dried-up
body”
or “mummy,” a rather unflattering description. Nonetheless, the human
skeleton is a triumph of design and engineering that puts most skyscrapers to
shame. It is strong, yet light, and almost perfectly adapted for the protective, locomotor,
and manipulative functions it performs.
Te
skeleton
, or
skeletal system
, composed of bones, cartilages, joints, and liga-
ments, accounts for about 20% of body mass (about 30 pounds in a 160-pound person).
Bones make up most of the skeleton. Cartilages occur only in isolated areas, such as the
nose, parts of the ribs, and the joints. Ligaments connect bones and reinforce joints,
allowing required movements while restricting motions in other directions. Joints, the
junctions between bones, provide for the remarkable mobility of the skeleton. We dis-
cuss joints and ligaments separately in Chapter 8.
PART 1
The Axial Skeleton
Name the major parts of the axial and appendicular skeletons and describe their
relative functions.
7
The Skeleton
PART 1
The Axial Skeleton
The Skull
(pp. 201–217)
The Vertebral Column
(pp. 218–224)
The Thoracic Cage
(pp. 224–227)
PART 2
The Appendicular
Skeleton
The Pectoral (Shoulder) Girdle
(pp. 227–228)
The Upper Limb
(pp. 228–234)
The Pelvic (Hip) Girdle
(pp. 234–238)
The Lower Limb
(pp. 238–243)
Developmental Aspects of the
Skeleton
(pp. 244–245)
199
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