Final answer:
Gas exchange in the lungs occurs through the process of passive diffusion, where molecules move from areas of higher concentration to areas of lower concentration without requiring energy. This allows oxygen to enter the bloodstream and carbon dioxide to be released. This process is facilitated by the large surface area of the alveoli in the lungs and the continuous flow of blood and breathing.
Step-by-step explanation:
Gas exchange occurs through the process of passive diffusion. This is when molecules move from areas of higher concentration to areas of lower concentration without requiring energy. In the context of gas exchange in the lungs, oxygen and carbon dioxide molecules naturally move down a concentration gradient, with oxygen moving into the bloodstream and carbon dioxide moving out. This process is facilitated by the large surface area of the alveoli in the lungs and the continuous flow of blood and breathing.