3.1.1b) The features of an efficient exchange surface

Question 1

Increased surface area

Answer 1

Provides area needed for exchange
Overcomes the limitations of the SA:V ratio of larger organisms

Question 2

Thin layers

Answer 2

The distances that substances have to diffuse are short, making the process fast and efficient

Question 3

Good blood supply

Answer 3

The steeper the concentration gradient, the faster diffusion takes place
Having a good blood supply ensures substances are constantly delivered to and removed from the exchange surface
This maintains a steep concentration gradient for diffusion

Question 4

Ventilation to maintain diffusion gradient

Answer 4

A ventilation system helps to maintain concentration gradients and makes the process more efficient