What structural characteristics of the aveoli make them an ideal site for the diffuesion of gases?

Question

please help


Why does oxygen move from the aveoli into the pulmonary capillary blood?

Answer 1

The alveoli of the lung are an ideal site for diffusion of gases because they are comprised of:

o An air space
o A thin walled membrane
o An adjacent capillary network

Oxygen moves into the capillary blood by diffusion - it moves from the air space where there is a high partial pressure into the de-oxygenated blood of the capillary where there is a low partial pressure.

CO2 moves in the opposite direction for the same reason.

Answer 2

Aveoli are super thin which makes diffusive exchange easier.

Oxygen will move into the blood because the concentration of oxygen outside is greater outisde than it is in the capillaries.