Bone Function and Development

Question 1

What are 5 functions of bone?

Answer 1

1) Centre of Bone Marrow
2) Protection
3) Transmittal of Body Weight
4) Allows movement (Joints inc)
5) Mineral Storage

Question 2

What are 5 types of bone?

Answer 2

1) Long Bone
2) Short Bone
3) Flat Bone
4) Irregular Bone
5) Sesamoid

Question 3

What are examples of each of bone types?

Answer 3

1) L: Humerus
2) Irregular: Vertebrae
3) F: Skull

Question 4

What are the 2 types of skeleton?

Answer 4

Axial: Skull and Trunk/Vertebrae
Appendicular: Limbs and pelvic girdles

Question 5

What are the functions and origins of Osteoblasts?

Answer 5

Origin: Mesenchymal Stem Cell
Function: Build bone by synthesising Osteoid (Type 1 Collagen Rich matrix)

Question 6

What is the role of osteoclasts and origin

Answer 6

Origin: Haematopoietic Stem Cell
Role: Resorption of bone, with lots of lysosomes

Question 7

What are osteocytes?

Answer 7

Less synthetically active osteoblasts trapped within bone (Osteoid mineralised by calcium hydroxyapatite)

Question 8

What are the main compositions of bone?

Answer 8

50-70% mineral
20-40% Organic material
10% Non-cellular proteins
5-10% H2O

Question 9

What are the microscopic different bone types?

Answer 9

1) Woven: Quickly made, disorganised with no clear structure

2) Lamellar: Slowly made with defined layer structure

Question 10

What are 5 reasons for remodelling of bone?

Answer 10

1) Replace woven for lamellar
2) Response to exercise
3) Repair damage
4) Obtain calcium
5) Form bone shape

Question 11

What 2 enzymes used in bone remodelling?

Answer 11

1) Collagenases

2) MMP’s (Matrix Metalloproteinase’s)