Question

what is alveoli explain about it

Answer 1

Alveoli are the tiny air sacs at the end of the smallest air passages in the lungs. There are millions of alveoli in each lung. ... The blood also passes carbon dioxide to the alveoli, to be breathed out. Each of our lungs has about 300 million alveoli. Oxygen passes from the alveoli into the bloodstream.

Answer 2

Alveoli are tiny sacs present in the lungs. They are connected to blood capillaries are helps to transfer oxygen and take carbon di oxide out of the blood. They increase the surface area of the lungs upto 70 million square cm which increase the absorption of gases through the lungs...
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