Here's why:
* Large surface area: Alveoli are tiny air sacs with a huge surface area, maximizing the area for gas exchange.
* Thin walls: The walls of alveoli are only one cell thick, allowing for easy diffusion of oxygen and carbon dioxide.
* Moist environment: The alveoli are kept moist, which helps gases dissolve and diffuse more readily.
* Close proximity to capillaries: A dense network of capillaries surrounds each alveolus, allowing for efficient exchange between the air and the bloodstream.
In summary: The unique structure of the alveoli, with their large surface area, thin walls, moist environment, and close proximity to capillaries, make them exceptionally well-suited for the diffusion of gases.
