The respiratory surface is a medium where gaseous exchange occurs a good respiratory surface purchase the following ;
- It most be moist to dissolve the gases
- It should be thin to allow for fast diffusion of gases or for short distances for gases to diffused
- It should be highly vascularized with blood capillaries to absorb and transport the gas.
- It should have a large surface area to increase the uptake of gases.
- It most be accessible to meet target organs so as to effect internal respiration.
- It should be permeable to allow the passage of gases.
