PATHOLOGY

Detailed explanation-1: -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-2: -While we breathe, we inhale oxygen along with nitrogen and carbon dioxide which co-exist in air. The inhaled air reaches lungs and enters alveoli where oxygen diffuses out from alveoli into blood, which enters into lungs via pulmonary capillaries, and carbon dioxide diffuses into alveoli from blood.