Answer: The lungs are well supplied with blood due to lots of capillaries covering the alveoli, constantly maintaining a large diffusion gradient, air is able to pass easily down this gradient due to the alveoli having very thin walls (one cell thick).
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The alveoli are adapted to make gas exchange in lungs happen easily and efficiently. Here are some features of the alveoli that allow this: they give the lungs a really big surface area. they have moist, thin walls (just one cell thick)
Hope this helps......... Stay safe and have a Merry Christmas!!!!!!!!!!! :D
