Norm bone function Flashcards
List some purposed of the skeleton
-Raises us from the ground against
gravity
- Determines basic body shape
-Transmits body weight
-Forms jointed lever system for movement
- Protects vital structures from damage
- Houses bone marrow
-Mineral storage (calcium, phosphorous, magnesium)
Discuss bone classification by shape
Long bones
- tubular shape with hollow shaft and ends expanded for articulation with other bones
Short bones
- cuboidal in shape
Flat bones
- plates of bone, often curved, protective function
Irregular bones
- various shapes
Sesamoid bones
- round, oval nodules in a tendon
What are the 2 different type of bone structure (macro view)
cortical - compact
trabecular - cancellous and spongy
what are the 2 types of bones structure (micro view)
woven
lamellar
what is norm mineral content for adult
50-70%
why do bones have wide ends
spreads load over weak, low friction surface
why are some bones hollow and long
why are some bones flat
protective
at what developmental age does bone remodelling occur
20-50
at what developmental age does bone modelling occur
0-20
what are the 2 divisions of skeleton
-appendicular -126
-axial -80
what are the cells of the bone
-Osteoclast
multinucleated
-Osteoblast
plump, cuboidal
-Osteocyte
stellate, entombed in bone
-Bone lining cell
flattened, lining the bon
Discuss the orginin of an osteblasts
mesenchymal stem cell –>osteo progenitor cell –> osteoblast –> other cell of the bone marrow and bone
Function of osteoblasts
-produce type 1 collagen
-deposotiee calcium
-high alkaline phosophtase activity
-build bone
what are the transcription factors present for mesenchymal to be an ostoprogenter
Osx, cbfa1 Wnts
