skeletal system Flashcards
functions of skeletal system
support
protection
movement
red blood cell and hormone production
mineral, growth factor, and fat storage
long bone
femur
flat bone
skull
short bone
metacarpals
irregular bone
vertebrae
sesamoid bone
patella
red bone marrow
red blood cell production
yellow bone marrow
stores fat
compact bone
dense outer layer
smooth and solid
contains osteons
found in the diaphyses of long bones
majority of skeleton
gives strength and support
stores calcium
spongy bone
honeycomb of flat pieces of bone deep to compact bone (trabeculae)
found at the ends of long bones, ribs, skull, pelvis, and vertebrae
helps make bones lighter
volkman’s cannal
connects blood vessels and nerves of the periosteum, medullary cavity, and central canal
runs perpendicular
lamellae
bony layers of osteon
collagen fibers allow resistance to twisting
canaliculi
tiny canals in osteon that connect lacunae to each other and central canal
osteocyte
mature bone cell that monitors and maintains the mineralized bone matrix
osteonic canal
aka haversian canal
houses blood vessels, lymphatic vessels, and nerves
runs parallel
osteoblasts
matrix synthesizing cell responsible for bone growth
osteoclasts
bone resorbing cell
intramembranous ossification
bone develops from fibrous membranes (flat bones)
osteoid is secreted by osteoblasts within the fibrous membrane and calcifies
spongy bone and periosteum form
compact bone replaces spongy bone
red marrow in spongy bone appears
endochondral ossification
bone formed by replacing hyaline cartilage (long bone)
interstitial growth
allows increase in the length of long bones
appositional growth
allows increase in bone thickness
osteoblasts beneath periosteum secrete bone matrix on external bone
osteoclasts remove bone on endosteal surface
importance of calcium
nerve transmission
muscle contraction
blood coagulation
cell division
secretion of glands and nerve cells
bone remodeling
in response to stress or hormones
growth hormone
most important in stimulating epiphyseal plate activity in infancy and childhood