AP BIOLOGY

Detailed explanation-1: -Expired air contains more carbon dioxide, it contains less oxygen, and it contains more water vapor than inspired air. The air we inhale, which is inspired air, comes from the atmosphere, which contains 21 percent oxygen.

Detailed explanation-2: -Water is formed when sugar (food) is broken by oxygen in respiration (along with carbon dioxide). As a result, exhaled air has significantly more water vapour than inhaled air.

Detailed explanation-3: -The percentage of CO2 in inhaled air is 0.04% whereas in exhaled air it is 4.4%. Therefore, we can say that exhaled air has more percentage of carbon dioxide than in the inhaled air.

Detailed explanation-4: -Note that not all of the oxygen in the air is taken up by the lungs and that the expired gases from the lungs are heated to body temperature and saturated with water vapor-thus the higher water vapor content of the expired air.

Detailed explanation-5: -Exhaled air contains less oxygen and less carbon dioxide than inhaled air.