When you are jogging, your muscles are using more oxygen and releasing more carbon dioxide into the blood than when you are at home on the couch. Which of the following would occur during your jog?
A) Blood pH would become more basic.
B) The concentration of bicarbonate ions (HCO3−) in the blood would decrease.
C) The medullary respiratory center would detect rising carbon dioxide levels.
D) The volume of the dead air space would decrease.

Question

Quizplus · Accepted Answer

During exercise, there is an increase in carbon dioxide production due to increased metabolism. This leads to an increase in carbon dioxide levels in the blood, which is detected by the medullary respiratory center in the brainstem, causing an increase in breathing rate and depth (hyperventilation) to expel the excess carbon dioxide. Choices A and B are incorrect as increased carbon dioxide would cause blood pH to become more acidic, and the concentration of bicarbonate ions to increase. Choice D is also incorrect as the volume of the dead air space would not change during exercise.

When You Are Jogging, Your Muscles Are Using More Oxygen