The primary job of the lungs in the human body is to facilitate the exchange of gases, specifically oxygen and carbon dioxide. When we inhale, air enters the lungs, where oxygen diffuses through the alveoli (tiny air sacs) into the bloodstream. Simultaneously, carbon dioxide, a waste product of cellular metabolism, diffuses from the blood into the alveoli to be exhaled. This gas exchange is critical for maintaining the body’s oxygen supply and regulating blood pH levels. The lungs also play a role in filtering out foreign particles, humidifying inhaled air, and maintaining overall respiratory health.