Adaptation of Air Sacs for Gaseous Exchange

 

Adaptation for all transport :

1) large number of alveoli -> vary large surface area

2) thin layer of epidthellium -> short distance for diffusion

Adaptation for diffusion :

3) moist, covered by mucus -> dissolve and diffuse rapidly

4) covered by network of capillary -> oxygen can delivered to body rapidly , CO2 can delivered out the body rapidly,  create steeply concentration gradient to fasten diffusion

5) low blood pressure in nearby capillary -> stay longer time for gaseous exchange