Question

why is alveoli in one cell thick?​

Answer 1

Thin walls - alveolar walls are one cell thick providing gases with a short diffusion distance. ... A large diffusion gradient - breathing ensures that the oxygen concentration in the alveoli is higher than in the capillaries so oxygen moves from the alveoli to the blood. Carbon dioxide diffuses in the opposite direction.

Answer 2

Answer:

Thin walls - alveolar walls are one cell thick providing gases with a short diffusion distance. ... A large diffusion gradient - breathing ensures that the oxygen concentration in the alveoli is higher than in the capillaries so oxygen moves from the alveoli to the blood. Carbon dioxide diffuses in the opposite direction

(copied from Googl*)