The effectiveness of an exchange surface can be increased by:
- Having a large surface area
- Having a thin membrane - provides a short diffusion path
- Having an efficient blood supply (in animals and humans) to move the diffusing substances away, and to maintain a concentration gradient.
- Being ventilated (in humans and animals) to maintain steep concentration gradients.
- Having a moist surface
- Having a partially permeable membrane.
Lungs are specially adapted to make gas exchange more efficient - they are made of clusters of alvioli.
- These tiny air sacs give the lungs a large surface area, which is important for the most effective diffusion of oxygen and carbon dioxide.
- They also have a rich blood supply, which maintains a concentration gradient in both directions.
- As a result, gas exchange takes place along the steepest concentration…