When you exercise intensely, your rate of gas exchange rises because

Question

Quizplus · Accepted Answer

When you exercise intensely, your muscles require more energy, which means they require more ATP. This increased energy production requires higher levels of oxygen, which is delivered to the muscles via the bloodstream. The mitochondria in the muscle cells are responsible for aerobic respiration, which requires oxygen as a reactant. Therefore, the rate of gas exchange rises as the muscle cell mitochondria require more oxygen. Choice A is incorrect because muscle contraction requires ATP, not oxygen, to occur. Choice B is incorrect because the amount of carbon dioxide produced during cellular respiration increases, not the amount required. Choice D is incorrect because the surface area-to-volume ratio of the lungs does not decrease during exercise.

When You Exercise Intensely, Your Rate of Gas Exchange Rises