What is the actual gas exchange between inhaled air and the blood occurs across the capillaries of the?

Gas exchange between inhaled air and the blood occurs across the capillaries of the alveoli in the lungs. Oxygen from the inhaled air diffuses through the thin alveolar walls into the blood, where it binds to hemoglobin in red blood cells. Simultaneously, carbon dioxide, a waste product of metabolism, diffuses from the blood into the alveoli to be exhaled. This efficient exchange is driven by differences in partial pressures of the gases.