ANATOMY

Detailed explanation-1: -The lungs and respiratory system allow us to breathe. They bring oxygen into our bodies (called inspiration, or inhalation) and send carbon dioxide out (called expiration, or exhalation).

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). This process, called gas exchange, is essential to life.

Detailed explanation-3: -Carbon dioxide diffuses from the cells into the blood. Deoxygenated blood is carried by the veins towards the heart. It enters the right side of the heart and is pumped into the pulmonary system. Carbon dioxide diffuses into the lungs and is expelled as we exhale.

Detailed explanation-4: -As you breathe, your body takes in oxygen and releases carbon dioxide. This released CO2 increases the concentration of CO2 in a closed room. Other sources of CO2 in a room include smoking, cooking using a gas or wood stove, and using fireplaces.

Detailed explanation-5: -nitrogen – 78% oxygen – 17% carbon dioxide – 4% other gases – 1%.