What is the percentage of carbon dioxide in exhaled air?
21%
0.04%
16.4%
4.4%
The correct option is D
4.4%
The percentage of carbon dioxide in exhaled air is more than the percentage of carbon dioxide in inhaled air. Inhaled air has about 0.04% of carbon dioxide. This is also the amount of carbon dioxide present in the atmosphere. The exhaled air contains all the carbon dioxide that is a by-product of the cellular metabolic processes. Hence, the percentage of carbon dioxide in the exhaled air is 4.4%.