MICROANATOMY

Detailed explanation-1: -Tiny air sacs at the end of the bronchioles (tiny branches of air tubes in the lungs). The alveoli are where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out.

Detailed explanation-2: -Healthy lungs have about 300 million air sacs in them. Each air sac is surrounded by a network of fine blood vessels (capillaries). The oxygen in inhaled air passes across the thin lining of the air sacs and into the blood vessels.

Detailed explanation-3: -(a) Alveolar sac—> is also known as alveoli.

Detailed explanation-4: -Alveolar sacs are pocketlike structures made up of several individual alveoli. The main function of theseof the alveoli is to get oxygen into the blood stream for transport to the tissues, and to remove carbon dioxide from the blood stream!