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

Question

Quizplus · Accepted Answer

During exercise, the demand for energy increases, and the muscle cells need to undergo oxidative phosphorylation to produce ATP. As a result, there is an increased need for oxygen to be delivered to the cells, and the heart rate and respiration rate increase to meet this demand.

Therefore, choice C is the correct answer as it describes the process that drives the increase in respiration rate and heartbeat speed during exercise.

During Exercise, the Increase in Respiration Rate and Heartbeat Speed