AP BIOLOGY

Detailed explanation-1: -Alveoli are tiny, balloon-shaped air sacs in your lungs. The function of the alveoli is to move oxygen and carbon dioxide (CO2) molecules into and out of your bloodstream. Alveoli are an important part of your respiratory system, which includes the parts of your body that help you breathe.

Detailed explanation-2: -Tiny air sacs at the end of the bronchioles (tiny branches of air tubes in the lungs).

Detailed explanation-3: -Animals breathe, oxygen and give out carbon dioxide.

Detailed explanation-4: -When you inhale (breathe in), air enters your lungs, and oxygen from that air moves to your blood. At the same time, carbon dioxide, a waste gas, moves from your blood to the lungs and is exhaled (breathed out).

Detailed explanation-5: -When an animal breathes, it takes in oxygen gas and releases carbon dioxide gas into the atmosphere. This carbon dioxide is a waste product produced by the animal’s cells during cellular respiration. Cellular respiration occurs in the individual cells.