Intramembranous Ossification

Question 1

What bones are formed from Intramembranous Ossification?

Answer 1

• Flat bones of skull
• Mandible
• Clavicle

Question 2

Tissue replacement occurs between which tissues during intramembranous ossification?

Answer 2

Mesenchymal CT membrane is replaced with osseous tissue

Question 3

Describe the differentiation process that occurs during intramembranous ossification

Answer 3

Mesenchymal cells differentiate to osteoprogenitor cells, which then become osteoblasts.

Question 4

Describe the function of osteoblasts in intramembranous ossification

Answer 4

Osteoblasts create SPONGY bone tissue, which then remodels into COMPACT bone where necessary

Question 5

What are the two potential functions of mesenchymal cells during intramembranous ossification?

Answer 5

• Mesenchymal cells can differentiate to osteoprogenitor cells
• Mesenchymal cells around the developing bone form the fibrous periosteum

Question 6

What are the four stages of intramembranous ossification?

D.F.E.F

Answer 6

1. Differentiation of osteoblasts within mesenchyme
2. Formation of bony spicules
3. Entrapment of blood vessels
4. Formation of spongy bone