AP BIOLOGY

ANIMAL PHYSIOLOGY

HUMAN CIRCULATION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
When we inhale, the air that enters the lungs is rich in ____
A
carbon dioxide
B
fresh air
C
water
D
oxygen
Explanation: 

Detailed explanation-1: -The amount of inhaled air contains 21% of oxygen and 0.04% of carbon dioxide, while the air we breathe out contains 16.4% of oxygen and 4.4% of carbon dioxide. This is because our cells use oxygen from the inhaled air to release energy and give out carbon dioxide as a byproduct.

Detailed explanation-2: -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-3: -Oxygen rich air rushes through spiracles into the tracheal tubes, diffuses into the body tissue, and reaches every cell of the body. Similarly, carbon dioxide from the cells goes into the tracheal tubes and moves out through spiracles.

Detailed explanation-4: -Inhalation is the process of taking in the air which is rich in oxygen. Breathing is defined as the process that moves air in (inhalation) and out of the lungs (exhalation).

Detailed explanation-5: -Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges. This contraction creates a vacuum, which pulls air into the lungs. Upon exhalation, the diaphragm relaxes and returns to its domelike shape, and air is forced out of the lungs.

There is 1 question to complete.