Exchange

Question 1

Why do we need specialised exchange surfaces?

Answer 1

• High metabolic demand
• Low SA:V Ratio
• Diffusion distance too long
• Increase uptake of O2 and removal of CO2 (waste products)
• Diffusion is not sufficient

Question 2

Why do we need blood?

Answer 2

To transport soluble substances e.g O2 around the body for uptake in muscles or removal of substances such as CO2.