Explain the ways in which the structure of alveoli is related to its function

The alveolar epithelium is a site of rapid diffusion, consequently it is very thin, only one cell thick, providing a short diffusion pathway.Alveoli have constant blood flow and ventilation, maintaining a steep concentration gradient between oxygen and carbon dioxide.Alveoli are covered by a network of capillaries, providing a large surface ares for diffusion and a rich blood supply.