Histology: Bone

Question 1

Diaphysis

Answer 1

Long shaft of bone

Question 2

Epiphysis

Answer 2

Ends of the bone

Question 3

What are osteoprogenitor cells derived from?

Answer 3

Mesenchyme

Question 4

Osteoprogenitor Cells

Answer 4

Undergo mitosis and develop

into osteoblasts

Question 5

Osteoblasts

Answer 5

Bone forming cells found on the surface of bone

Question 6

Do osteoblasts have mitotic ability?

Answer 6

NO

Question 7

Osteocytes

Answer 7

Mature bone cells derived from osteoblasts that do not secrete matrix but exchange nutrients and waste

Question 8

Osteoclasts

Answer 8

Bone resorbing cells that work on growth, maintenance an bone repair

Question 9

When does cartilage formation and ossification occur in the embryo?

Answer 9

6th Week

Question 10

Intramembranous Ossification

Answer 10

• Flat bones of the skull and mandible are formed in this way
• “Soft spots” that help the fetal skull pass through the birth canal later become ossified forming the skull

Question 11

Endochondral Ossification

Answer 11

• The replacement of cartilage by bone

- Most bones of the body are formed in this way including long bones

Question 12

Appositional Growth

Answer 12

Growth of a bone by addition of bone tissue to its surface

Question 13

What is the mechanism of appositional growth?

Answer 13

• Bone is resorbed at endosteal surface and added at periosteal surface
• Osteoblasts–add bone tissue to the external surface of the diaphysis
• Osteoclasts–remove bone from the internal surface of the diaphysis