Gas Exchange Theory

The Gas Exchange Theory describes how oxygen from the air we breathe enters our blood, and carbon dioxide from our blood is expelled into the air. This process mainly occurs in the lungs, where tiny sacs called alveoli facilitate diffusion—oxygen moves from the alveoli into blood vessels, and carbon dioxide moves from blood into the alveoli to be exhaled. This exchange is vital for maintaining the body’s energy and removing waste gases, ensuring cells receive enough oxygen for metabolism and that waste gases are effectively removed.