How does the structure of alveoli maximize gas exchange?

I know alveoli are where oxygen and carbon dioxide are exchanged in the lungs, but what is it about their structure that makes them so efficient? How do things like surface area, thin walls, and blood supply contribute to their function? Are there diseases that specifically affect alveolar structure?

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Replies (3)

@john_smith23

Alveoli are tiny sacs with super thin walls and a huge combined surface area. This lets oxygen and carbon dioxide diffuse quickly between the air and blood.

18 days ago

@lucyowen_14

Each alveolus is surrounded by capillaries, so there’s a very short distance for gases to travel. The moist surface also helps gases dissolve and diffuse more easily.

18 days ago

@ninaking74

Diseases like emphysema destroy alveolar walls, reducing surface area and making gas exchange less efficient. That’s why people with lung disease get short of breath so easily.

18 days ago