Bone cells

Question 1

What are 3 main bone cell types?

Answer 1

1) Osteoblast
2) Osteoclast
3) Osteocyte

Question 2

Function osteoblast, osteoclast, osteocyte

Answer 2

Osteoblast- build cells
Osteoclast- break cells
Osteocyte- energy and phosphate metabolism

Question 3

What forms: osteoblast, osteoclast, osteocyte?

Answer 3

Osteoblast- mesenchymal stem cell
Osteoclast- haematopoietic stem cell
Osteocyte- mesenchymal stem cell (derived osteoblasts)

Question 4

What are osteocytes derived from?

Answer 4

Osteoblasts

Question 5

Explain formation osteoblasts?

Answer 5

1) Mesenchymal osteoblast progenitor
2) Osteoblast precursor
3) Active osteoblast

Question 6

Explain formation osteoclasts?

Answer 6

1) Haematopoietic osteoclast progenitor
2) Osteoclast precursor (RANK ligand added)
3) Mononuclear osteoclast (RANK ligand added)
4) Quiescent osteoclast (RANK ligand added)
5) Active osteoclast

Question 7

Function RANK ligand?

Answer 7

Manage osteoclast formation

Question 8

What is precursor to osteoblasts?

Answer 8

Osteogenic cells

Question 9

Where are osteogenic cells located?

Answer 9

Periosteum and marrow

Question 10

Function of osteoblast?
Location

Answer 10

Bone formation
Located- periosteum and endosteum

Question 11

Function osteocytes?
Location?

Answer 11

Maintain mineral conc of matric
Located- trap in matrix

Question 12

Function osteoclasts?
Location?

Answer 12

Bone reabsorption
Line bone- site injured or old bone

Question 13

Name type cell?

Answer 13

1) Osteoblast- plump, cuboidal
2) Osteoclast- multinucleate
3) Osteocyte

Question 14

What is origin of osteoblasts?

Answer 14

Mesenchymal

Question 15

Explain maturation of osteoblasts?

Answer 15

1) Mesenchymal in origin
2) Converted into progenitor cell
3) Form numerous- osteoblasts, chondrocytes

Question 16

What regulates osteoclasts?
Where secreted?

Answer 16

Osteoblasts secrete rank ligand

Question 17

State functions of osteoblasts? (3)

Answer 17

1) Form bone- osteoid
2) Prod type 1 collagen- min ECM by deposit hydroxyapatite
3) Secrete factors regulate osteoclasts- Rank Ligands

Question 18

Where are osteoclasts derived from?

Answer 18

Hematopoietic stem cell

Question 19

Function rank ligand?

Answer 19

Regulate osteoclast formation (increase)

Question 20

What prevents formation osteoclasts?

Answer 20

OPG
Binds to RANKL and blocks its activity- inhibit osteoclast diff and bone resorption

Question 21

Function OPG?

Answer 21

Inhibit RANK ligand
Prevent bone resorption (by osteoclasts)