The bone cell types

Question 1

Osteogenic cells

Answer 1

Osteoprogenitor cells
bone specific stem cells develops into an osteoblast
- arise from mesenchymal stem cells (multipotent stromal cells)
- located in the periosteum (the outer layer) and endosteum (the surrounding of the spongy cell)

functions:
- divide to produce osteoblasts
- important in maintenance
- repairing fractuers

going through its own mitosis & help to protect (maintain) the bone itself (bone matrix)

Question 2

Osteocytes

Answer 2

: mature bone cell lives in lacunae = mechanosensory
- maintain bone tissues

1) secrete osteoid; control mineral deposition
- build bone
2) secrete acid phosphate
- dissolve bone
(repair microfractures) * crucial in healing density

functions:
bone turnover: maintain the protein & mineral content
(regulate bone density by releasing chemicals that inhibits osteoclasts & stimulates the osteoblast activity (making bones)

Bone repair: if exposed by a break, osteocytes are thought to release chmeicals that stimulate bone formation by stimulating osteoblasts

Question 3

Osteoblast

Answer 3

Immature bone cells located in the periosteum
= bone builder (forms bone extracellular matrix)

• secrete the organic component of matrix = osteoid (90% collagen + sugar compounds = osteocalcin protein + chondroitin sulphate)
• Increase calcium phosphate levels to ossify/ harden matrix

Question 4

Osteoclasts

Answer 4

In white blood cells
- crushing (dissolves the matrix)
- located in Howship’s lacunae found throughout surfaces of bone (periosteum & endosteum)

functions:
- bone resorption & homeostasis of minerals in bodily fluid
= secrete acids & proteolytic enzymes - osteolysis (breaking the bones)