AP BIOLOGY

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: -Explanation: The spherical or grape-like shape of the alveoli allows for maximum contact between the alveoli and the capillaries that surround them.

Detailed explanation-3: -The alveoli form clusters, called alveolar sacs, that resemble bunches of grapes. By the same analogy, the alveolar ducts leading to the sacs are like the stems of individual grapes, but, unlike grapes, the alveolar sacs are pocketlike structures made up of several individual alveoli.

Detailed explanation-4: -Each alveolus is cup-shaped with very thin walls. It’s surrounded by networks of blood vessels called capillaries that also have thin walls. The oxygen you breathe in diffuses through the alveoli and the capillaries into the blood.

Detailed explanation-5: -An alveolus is an anatomical structure that has the form of a hollow cavity. Its plural is alveoli, from the Latin alveolus, meaning little cavity.