Postnatal Bone Growth

Question 0

What are the 3 Functional Zones in Long Bone Growth?

Answer 0

1. Growth zone
2. Transformation zone
3. Osteogenic zone

Question 1

Growth in length on the long bones occurs where?

Answer 1

In the cartilage in the epiphyseal plate abutting the diaphysis of the bone.

Question 2

What occurs in the growth zone?

Answer 2

Cartilage cells undergo mitosis, essentially pushing the epiphyses away from the diaphysis.

Question 3

What occurs in the transformation zone?

Answer 3

Older cartilage cells enlarge, the matrix becomes calcified, cartilage cells die, and the matrix begins to deteriorate.

Question 4

What occurs in the Osteogenic zone?

Answer 4

New bone formation occurs where cartilage matrix deteriorated.

Question 5

What type of growth occurs in the width of long bones?

Answer 5

Apposition all growth: bone is added by osteoblasts at the periosteal surface and reabsorbed by osteoclasts at the endosteal surface.
Allows for thicker, stronger bones without being too heavy.