Question

Birds have air sacs give reason​

Answer 1

Explanation:

Air sacs serve as internal compartments which hold air and facilitate internal air passage to allow birds to have a continuous flow of large volumes of air through the lungs as a way to increase oxygen exchange capacity and efficiency.

Answer 2

Answer:

Air sacs serve as internal compartments which hold air and facilitate internal air passage to allow birds to have a continuous flow of large volumes of air through the lungs as a way to increase oxygen exchange capacity and efficiency.

Explanation:

The air sacs permit a unidirectional flow of air through the lungs. Unidirectional flow means that air moving through bird lungs is largely 'fresh' air and has a higher oxygen content. Therefore, in bird lungs, more oxygen is available to diffuse into the blood.