Skeletal System Flashcards
what are the 5 main function of bone?
- strucural support
- locotmotion
- protection
- blood formation
- mineral storage
what is the 2 compostion of the bone what makes up those 2 compostions ?
- organic- cells, matrix, fibres
- inorganic- is rigid hard and mineral salts like calcium crystals
what is the anatomy of the long bone and what are the 3 parts do and composed of?
- Soft spongy bone that is red marrow and where RBC forms
- diaphysis is yellow marrow fat )and - has medullary cavity and forms RBC under extreme conditions
- compact bone- hard and is the outer layer
what is the 5 structure organiation of the compact bone ?
- lamellae
- lacunae cavities between lamellae
- osteocyteds in lacunae
- canaculi - tiny canals
- haversian system- structural unit
what are osteoblast and what do they do?
osteoblast synthesize collagen fibres and coat bones with mineral and
overall build and repair bone and store minerals, decreases calcium in blood
what are osteocytes and where are the found
they are inactiviated osteoblast trapped in lacunae
what are osteoclasts ?
oseocytes breakdown or minerlize bone and increase the calcium in blood
when does bone remodeling occur and when is peak bone mass ?
in the skeleton every 10 years at the age of 18 years
what are 4 factors that affect remodelling ?
- stress- weight gain heavy load ,
- nutrition - increase in calcium more more bone
- genetics- 70% is of bone mass is dependant on genetics
- hormones
what are hormones affect on bone formations?
parathyroid hormones and calcitonin control osteroclast activity
what are the 3 age related changes in bone
- loss of calcium - more common in women starts at 30
- imbalance of protein and minerals 3. bone resorpton(break down) faster tha replacement -weaker
what are 3 cause of loss of of. calcium in the bone ?
- decrease in acitivty of osteoblast wit age
- hormones
- AGEs, free radicals
what is osteroporosis ?
it is porous bones where we have extreme lose of bone faster than new formation detected by x ray
what are the two type of osteo porosis ?
type 1. post menopausal osteoporiss- women after meno pause with decreased estrogen levels
type 2 : senile osteoporosis (vita D)
people ages 70 -80 signifant losss of cortical bone
what are 2 statistics on osteoporosis ?
- affects 24 mil americans
- 80% are women
- rate drastically increases after meno pause
what type of fractures does type 1 ostero porosis lead to ?
- vetebral fracture in spine 90 % occur in women , decreased mobility
- hip fractures
what are 4 prevetentive methods of type 1 osteoprosis ?
- calcium
- vit D
3.estrogen therapy - exercies
