Histo 6 bone histology Flashcards
Need to go over periosteal bone growth and bone remodeling
1
Q
Where does hematopoiesis occur in adults?
in infants? where in bones does this occur?
A
2
Q
Differences between compact and spongy bone?
A
3
Q
Woven bone
A
4
Q
Lamellar bone
A
5
Q
What is bone made up of?
A
6
Q
osteoprogenitor cells
A
7
Q
osteoblasts
A
8
Q
Osteocytes
A
9
Q
Osteoclasts
A
10
Q
Osteoclast differentiation
A
- Monocyte from bone marrow reaches area of bone formation and remodeling (M-CSF receptor on surface)
- Macrophage now. M-CSF ligand binds to M-CSF causes expression of RANK
- osteoblast expresses RANKL which binds to RANK this commits macrophage to osteoclastogenesis (osteoclast precursor)
- Resting nonfunctional osteoblast uncouples from osteoblast
- Maturation of osteoclasts is completed when the sealing zone and border appear via apha beta integrin
11
Q
Osteoclast differentiation simpler
A
- Monocyte w/ M-CSF receptor
- Macrophage M-CSF ligand binds it (osteoblast)
- expresses RANK now
- Osteoblast has RANKL which bind RANK
- osteoclast precursor
- release from osteoblast (resting)
- sealing zone and ruffled border
- via integrin creates functional osteoclast
12
Q
How are osteoclasts regulated?
A
osteoblasts has a RANKL decoy protein (osteoprotegerin) which blocks RANKL binding to RANK
this regulates number of active osteoclasts
(control differentiation not function)
13
Q
A
14
Q
Periosteum
A
does not cover articular surfaces
15
Q
endosteum
A