Ch. 7.4 Skeletal System Key Terms
appendicular skeleton
Forms the extremities (limbs) and is composed of the shoulder girdle, arm bones, pelvic girdle, and leg bones.
axial skeleton
Forms the main trunk of the body and is composed of the skull, spinal column, ribs, and breastbone.
carpals
The 8 bones of the wrist.
clavicles
The two collarbones (part of the shoulder girdle).
cranium
The spherical structure that surrounds and protects the brain.
diaphysis
diaphysis: The long shaft of a long bone.
endosteum
endosteum: A membrane that lines the medullary canal and keeps the yellow marrow intact. It also produces some bone growth.
epiphysis
epiphysis: The two extremities (ends) of a long bone.
femur
femur: The thigh bone (upper leg bone).
fibula
fibula: The slender, smaller bone of the lower leg.
fontanels
fontanels: Spaces, or "soft spots," in the cranium at birth that are made of membrane and cartilage, allowing for skull enlargement. They turn into solid bone by approximately 18 months of age.
foramina
foramina: Openings in bones that allow nerves and blood vessels to enter or leave the bone.
humerus
humerus: The upper arm bone.
joints
joints: Areas where two or more bones join together.
ligaments
ligaments: Connective tissue bands that help hold long bones together at joints.
medullary canal
medullary canal: A cavity in the diaphysis (long shaft) of a long bone. It is filled with yellow marrow.
metacarpals
metacarpals: The 5 bones that form the palm of the hand.
metatarsals
metatarsals: The 5 bones that form the instep of the foot.
os coxae
os coxae: The two coxal, or hip, bones (part of the pelvic girdle).
patella
patella: The kneecap.
periosteum
periosteum: The tough membrane that covers the outside of a bone, necessary for bone growth, repair, and nutrition.
phalanges
phalanges: The bones of the fingers and toes.
radius
radius: The lower arm bone on the thumb side that rotates around the ulna.
ribs
ribs: There are 12 pairs that attach to the thoracic vertebrae. The first 7 pairs are true ribs.
scapulas
scapulas: The two shoulder bones (part of the shoulder girdle).