Did You Know!
The primary function of the lungs is to facilitate the exchange of oxygen and carbon dioxide between the air we breathe and the bloodstream. Oxygen from inhaled air diffuses across the thin walls of the air sacs (alveoli) into the surrounding capillaries, where it binds to hemoglobin in red blood cells for transport to tissues throughout the body. At the same time, carbon dioxide produced by cellular metabolism diffuses from the bloodstream into the alveoli to be exhaled.