4. Which best explains the function of the alveoli in the respiratory system?
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A. The alveoli help to keep the lungs healthy by providing a way for all the cells
in the lungs to obtain nutrients from the bloodstream
B. The alveoli help to keep the lungs inflated when you breathe out and make it
possible to absorb oxygen
C. The alveoli provide a large surface area for absorbing oxygen from the air and
releasing carbon dioxide wastes from the bloodstream
D. The alveoli provide a large surface area for absorbing oxygen from the air
when you breathe in and look like a bunch of grapes
a

Alveoli are tiny functioning structures that compose your lungs. They help with respiration. They have a large total surface area, which is very useful for respiration. The more surface area there is, the more transactions can happen. Which means that breathing will be easier/faster when you have more alveoli. (Please rate this answer if you have time!)

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