Where does oxygenation occurs in the body?

Oxygenation occurs in the lungs, specifically in the alveoli. The alveoli are small air sacs in the lungs where gas exchange takes place. When we inhale, oxygen-rich air enters the lungs and diffuses into the alveoli. At the same time, carbon dioxide, a waste product of cellular respiration, diffuses out of the alveoli and is exhaled. The oxygen that diffuses into the alveoli is then transported throughout the body by the bloodstream.