During exercise,the increase in our respiration rate and heartbeat speed is driven by the need to replenish the oxygen used to support
A) lactic acid fermentation.
B) carbon dioxide synthesis in our lungs.
C) oxidative phosphorylation in muscle cell mitochondria.
D) the dark reactions of photosynthesis.

Question

Quizplus · Accepted Answer

During exercise, our muscle cells require more energy than usual, which is generated by oxidative phosphorylation in the mitochondria. This process utilizes oxygen to produce ATP, which fuels muscle contractions. The increased demand for ATP during exercise drives an increased respiration rate and heartbeat to deliver more oxygen to the muscles and remove waste products like carbon dioxide. Lactic acid fermentation occurs in the absence of oxygen and is not the primary source of energy during exercise. The dark reactions of photosynthesis occur in plants, not in animals.

During Exercise,the Increase in Our Respiration Rate and Heartbeat Speed