The Skeletal System

Front 1

functions of the skeletal system

Back 1

support, protection of soft organs, movement, storage of minerals and fats, blood cell formation.

Front 2

long bones

Back 2

longer than wide, mostly compact bone, shaft with heads at both ends. eg. femur and humeus.

Front 3

short bones

Back 3

cube shaped, mostly spongy bone. eg. carpals and tarsals.

Front 4

flat bones

Back 4

thin, flat, and curved. thin layers of compact bone around a layer or spongy bone. eg. skull, ribs, and sternum.

Front 5

irregular bones

Back 5

irregular shape. do not fit into to other bone classification categories. eg. vertebrae and pelvis.

Front 6

major areas of a long bone

Back 6

diaphysis- shaft. made of compact bone.
epiphysis- ends of bone. made of spongy bone.
periosteum- outside covering of diaphysis. fibrous connective tissue membrane. inner osteogenic layer composed of osteoblasts and osteoclasts.
endosteum-delicate membrane covering internal surfaces of bone.
articular cartilage- covers the external surface of the epiphyses. made of hyaline cartilage. decreases friction at joint surfaces.
medullary cavity- cavity of shaft. yellow marrow (fat) in adults. red marrow (blood cell formation) in infants.

Front 7

microscopic areas of a long bone

Back 7

osteon (haversian system)- unit of bone.
central (haversian) canal- opening in the center of an osteon. carries blood vessels and nerves.
lamellae- rings around the central canal. sites of lacunae (contain bone cells osteocytes).
canaliculi- tiny canals. radiate from central canal to lacunae. form a transport system.

Front 8

growth of a long bone

Back 8

epiphyseal plates allow for growth during childhood. new cartilage is continuously formed. old cartilage becomes ossified (converting to bone tissue). cartilage broken down, bone replaces cartilage.

Front 9

bone remodiling

Back 9

bones change shape. grow in width. adjacent osteoblasts and osteoclasts deposit and reabsorb bone at periosteal and endosteal surfaces.

Front 10

bone salts

Back 10

calcium phosphate- gives bones hardness and resistance

Front 11

organic matrix

Back 11

collagen- gives bones flexibility.

Front 12

main bones of the skeleton

Back 12

clavicle, scapula, sternum, rib, humerus, vertebra, radius, ulna, carpals, phalanges, metacarpals, femur, patella, tibia, fibula, tarsals, metatarsals.

Front 13

fibrous joint

Back 13

no joint cavity. immovable. allows more movement than sutures.