Bone Growth

Question 1

What are the 2 types of Bone Formation

Answer 1

1) Intramembraneous ossification

2) Endochondral ossification

Question 2

Intramembranous Ossification

Answer 2

Bone formation

• transformation of condensed mesenchymal tissue into bone tissue by differentiation of mesenchymal cell into osteoblasts. And depositing of osteopenia
• Flat bones=skul

Question 3

Endochondral Ossification

Answer 3

Bone development with a hyaline cartilage model

• bones of extremities and weight bearing bones
• initial bone formation occurs during fetal life
• as development continues cartilage models of bone are replaced by osseous tissue

Question 4

What do the two types of bone growth have in common?

Answer 4

Both give rise to immature bone

-both have compact and spongy bone components

Question 5

Intramembranous ossification steps

Answer 5

Occurs through activity of the periosteal membrane tissue
ALL OCCURS AT PRIMARY. OSSIFICATION CENTER
1) Condensation of mesenchyma cells into nodules where bone is destined to be formed
2) Mesenchumal cells differentiate into osteoprogenitor cells
3) Increased vascularization
4) Osteoprogenitor cells differentiate into osteoblasts
5) Osteoblasts secrete osteoid trapping osteoblasts which become osteocytes
6) Osteoid turns into thick spicules after mineralization called WOVEN bone
7) Cells become more separated but remain attached by cytoplasmic processes
8) Woven bone-> Lammelar bone

Question 6

Osteoid

Answer 6

Unmineralized bone matrix

-type 1 collagen and bone matrix proteins

Question 7

Immature Bone

Answer 7

Nonlamellar-bundle or woven bone
-lacks Haversian Systems

• More cells/unit area
• cells in random orientation
• more basophils than mature bone
• grows more rapidly than mature bone
• can remain in adults in the alveolar socket (where teeth are), some tendon insertions, and area of remodeling

Question 8

Lamellar bone

Answer 8

Mature Bone

-Has haversian systems