Requirement for effective gaseous exchange

• The gaseous exchange surface must be large; to maximise gaseous exchange
• The gaseous exchange surface must be thin; for quick and easy diffusion
• The gaseous exchange surface should be moist; gases (O2 AND CO2) must be in solution in order to diffuse through a membrane
• The gaseous exchange surface must have a transport system; for efficient transport of gases
• The gaseous exchange surface must be well protected; it is very thin and fragile