Lecture 6

Question 1

What is a bone?

Answer 1

• Bones has cells
• Bone grows
• Bone remodels (to remain strong, response to external pressure)
• Bone can repair itself

Question 2

What is the composition of bone tissue?

Answer 2

Connective tissue

Question 3

What makes up connective tissue?

Answer 3

Cells and Extracellular matrix.

Question 4

What are the two components of the extracellular matrix?

Answer 4

Organic Compounds
> 33% of matrix
> Collagen (protein)
> Ground substance (proteoglycans)
> Function = resists tension

Inorganic Compounds
> 67% of matrix
> Hydroxyapatite (mineral salts)
> Hardness 
> Function = resists compression

Question 5

What are the 3 bone cell types called?

Answer 5

Osteoblasts
> build ECM

Osteocytes
> mature bone cells

Osteoclasts
> break down of ECM

Question 6

What are the cells involved in making loose and dense connective tissue?

Where are loose connective tissues found and for what purpose?

In terms of density, why does loose connective tissue slightly stretch?

Answer 6

Fibroblasts

Under the skin to limit stretching

It has a low density.

Question 7

What are fibroblasts?

Answer 7

Relatively undifferentiated cells that secrete collagen

Question 8

What types of fibres have high tensile strength?

Answer 8

Collagen fibres

Question 9

Where are dense connective tissues found and for what purpose?

Answer 9

Tendons
Ligaments
Cartilage
Bone

Resist stretch in linear direction.