Ch. 7.4 Skeletal System Key Terms
forms the extremities and is composed of the shoulder gridle, arm bones, pelvic gridle, and leg bones
appendicular skeleton
the long shaft
diaphysis
“soft spots” that allow the enlargement of the skull as brain growth occurs
fontanels
a cavity in the diaphysis
medullary canal
the outside of bone is covered with a tough membrane and contains blood vessels, lymph vessels, and oteoblasts, special cells that form new tissue
periosteum
forms the main trunk of the body and is composed of the skull, spinal colum, ribs, and breastbone
axial skeleton
a membrane that lines the medullary canal and keeps the yellow marrow intact
endosteum
openings in the bones that allow nerves and blood vessels to enter or leave the bone
foramina
5 palm of the hand bones
metacarpals
14 (3 on each finger and 2 on the thumb)
phalanges
8 wrists
carpals
two extremities, or ends
epiphysis
bones of each arm include 1 upper arm
humerus
5 instep of foot
metatarsals
1 lower arm on the thumb side that rotates around the ulna to allow the hand to turn freely
radius
shoulder, or pectoral, girdle is made of two collarbone
clavicles
each leg consists of 1 thigh
femur
areas where two or more bones join together
joints
pelvic girdle is made of two coxal or hip, bones, which join the sacrum on the dorsal part of the body
os coxae
found in certain bones such as vertebrae, ribs, sternum, and cranium in the proximal ends of the humerus and femur
red marrow
the spherical structure that surrounds and protects the brain
cranium
1 slender, smaller bone of the lower leg that attaches to the proximal end of the tibia
fibula
connective tissue bands that help hold long bones together at the joints
ligaments
1 kneecap
patella
12 pairs
ribs