Bone Cells

Question 1

List the Four types of Bone Cell

Answer 1

Osteoblasts - Bone Building Cell
Osteocytes - Mature Bone Cells
Osteoclasts - Bone Reabsorbing Cells
Lining Cells - Line the surface of bone

Question 2

What are Osteoblasts

Answer 2

• Cells responsible for the production of new Bone (process known as Osteogenesis)
• Present at sites where bone is growing, repairing and remodelling
• Osteoblasts deposit new bone tissue around themselves and eventually become trapped in tiny pockets known as Lucunae
• It is at this point that they diffrentiate into Ostoecytes (Mature Bone Cell)

Question 3

What are Osteocytes

Answer 3

• Mature Bone Cells that do not divide
• Monitor and maintain mature bone tissue
• Detect mechanical strain
• Regulate the balance of calcium and Phosphate because they signal ostoeblasts

Question 4

What are Osteoclasts

Answer 4

• Giant Cells with 50 or more nuclei
• Cells Break down releasing calcium and phosphate
• Help regulate calcium and phosphate concentrations in body fluids
• Found in areas of the bone where there is active growth

Question 5

Osteoblasts are present at which sites of the Bone

Answer 5

• Periostium
• Each end of the Diaphysis of the long bone
• At Fracture sites

Question 6

Osteoclasts are found in which parts of the bone

Answer 6

• Areas where growth and repair occur
• Periosteum - maintaining bone shape and removing excesss callus formed during fracture healing
• Medullar Cavity - during growth and canalising of the bone when healing

Question 7

Describe what is meant by the bone matrix

Answer 7

Material between the living Bone cells
Organic material - Collagen
In organic Material:
* Calcium/bone salts
* Hydropoxyapitate crystals

Question 8

What are Lining Cells

Answer 8

• Line the entire surface of the bone unless osteoid is present (unmineralized bone)
• Release of Calcium from bone
• Protects bone from chemical
• Can sometimes inhibit drugs from curing bone infection

Question 9

What is osteoid

Answer 9

Unmineralized organic component of Bone matrix
Made up of Type 1 collagen and bone matrix proteins
Eventually undergoes calcification and mineralization to form lamelle/layers in the bone matrix (Part of mineralization/hardening of the bone)

Question 10

What is the other name given to compact bone

Answer 10

Cortical Bone

Question 11

What is the name of the intercellular bone constituent which consists of ground substance, collagen fibers and inorganic mineral salts

Answer 11

Bone Matrix

Question 12

What are Interstitial lamellae

Answer 12

• Sit in between Osteons/Haversion systems
• extracellular matrix around the cells that gives compact bone its hardness and rigidity

Question 13

Which bone cell has multiple nuclei

Answer 13

Osteoclast