Question

Give reason: Air sacs are thin walled and many in numbers​

Answer 1

Answer:

Air sacs have thin walls to help the exchange of air between the cell and the exterior environment so as the sacs have thinner walls, it helps move the oxygen or air through the wall easily. And there are so many air sacs because they are the places where exchanges of air in the circulatory system take place. These air sacs are known as ALVEOLI.

Answer 2

Explanation:

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