NEET BIOLOGY

Detailed explanation-1: -Oxygen molecules attach to red blood cells, which travel back to the heart. At the same time, the carbon dioxide molecules in the alveoli are blown out of the body the next time a person exhales. Gas exchange allows the body to replenish the oxygen and eliminate the carbon dioxide. Doing both is necessary for survival.

Detailed explanation-2: -Breathing is the process of taking in air containing oxygen (called inhaling) and letting out air that contains carbon dioxide (called exhaling).

Detailed explanation-3: -They bring oxygen into our bodies (called inspiration, or inhalation) and send carbon dioxide out (called expiration, or exhalation). This exchange of oxygen and carbon dioxide is called respiration.

Detailed explanation-4: -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-5: -When we breathe in air it contains oxygen reaches the lungs. There the gaseous exchange takes place. The air which we breathe out contains carbon dioxide.