ANATOMY

Detailed explanation-1: -Inhaled air is a mixture of different gases present in the atmosphere. It contains around 78% nitrogen, 21% oxygen, 0.04% of carbon dioxide and other gases.

Detailed explanation-2: -The atmospheric air consists of 78% of nitrogen, 21% of oxygen, 0.04% of carbon dioxide and 0.93% of argon and other inert gases.

Detailed explanation-3: -The air that we inhale contains around 21% oxygen. This oxygen is used by the body for respiration and therefore the exhaled has less percentage of oxygen (13.6% to 16%).

Detailed explanation-4: -The percentage of oxygen in inhaled air is 21%.

Detailed explanation-5: -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.