Ch 2 Flashcards
Functions of the skeletal system
hematopoiesis protection calcium stores structure movement
Building blocks of bones
Osteogenic cell
>osteoprogenitor cell
»osteoblast
»>osteocyte
Breaking-down-block of bones
(Osteoclast-inducing cytokines
>macrophages)
»osteoclasts
Function:
osteoprogenitor cell
cell that turns into osteoblast
Function:
osteoblast
matrix-synthesizing cell
Function:
osteocyte
mature bone cell that maintains the bone matrix
Function:
osteoclast
breaks bone down
Why would bone want to be broken down?
- fracture repair
- strengthen when repeatedly stressed
- to release Ca++ for use
Extracellular matrix types
mineralized collagen
composite material
Features of mineralized collagen
•hydroxyapatite: compression strength/ impact force
Features of composite material
•collagen fibers: tensile strength
Structure of bone:
cortical
compact, dense formation of osteons
-covers the outside of all bones
Structure of bone:
cancellous or trabecular
spongey, formation of small columns
-made to absorb force
Types of bones
Long, Short, Flat, Irregular
Features of bone:
Epiphysis?
Diaphysis?
Epiphysis: ends of bone
Diaphysis: separate epiphysis
Features of bone:
Periosteum?
Medullary cavity?
Periosteum: wrapping of the outside of bone
-connecting site
Medullary cavity: is the central cavity of bone shafts
-red bone marrow and/or yellow bone marrow (adipose tissue) is stored
Bone Loss:
Osteoporosis?
Osteopenia?
Osteoporosis:
bones with very low density
Osteopenia:
bones with blow avg density
Peak bone mass occurs at what age?
about 30yrs
What sex has the more bone loss? Why?
Females experience more bone loss than males.
Menopause, lower peak bone mass..
