bone physiology Flashcards
(40 cards)
bone functions
support weight of body body position and movement protection mineral storage blood and fat production
bone characteristics
light, but stronger than reinforced concrete / can be remodeled or reshaped depending on metabolism or activity
2/3 of bones weight
calcium phosphate Ca3(PO4)2
1/3 of bone weight
collagen fibers
2% of bone weight?
cells like osteocytes
4 categories of bone
short, long, irregular, flat
short bones
length and width are close to equal (phalanges)
long bone
longer than they are wide (femur, humerus)
irregular bone
complex shapes (vertebrae, sphenoid)
flat bones
thin and broad (occipital, sternum)
diaphysis
shaft with marrow cavity inside
bone marrow
red marrow makes blood
yellow marrow makes fat
epiphysis
expanded portions at each end of the long bone
compact bone
where the bone is relatively solid
spongy bone
has air spaces within it
trabecula are the crossbars
periosteum
outer layer of bone which interacts with tendons, ligaments, and cartilage
endosteum
inner layer of compact bone
osteocytes
maintenance - mature bones cells, regulate calcium, aid in repair
osteoclasts
dissolve bone
osteoblasts
produce new bone
remodeling
the process of osteoblasts and osteoclasts breaking down and rebuilding bones
osteogenesis imperfecta
brittle bone disease - fragile and break easily
epiphyseal plates
growth plates - at end of diaphysis - continue growth in length - close by age 18 in girls and 20 in guys
simple or closed fractures
fractures where skin is intact