Ava conducted an experiment to determine respiratory rates during different activities. She counted the number of breaths per minute. Ava noted that the number of breaths increases as physical activity increases. Why is there an increase in the number of breaths per minute as activity increases?

Question

Responses

As activity increases, more oxygen is exhaled.

As activity increases, more oxygen is exhaled.

As activity increases, breathing becomes more efficient.

As activity increases, breathing becomes more efficient.

As activity increases, the oxygen needs of cells increase.

As activity increases, the oxygen needs of cells increase.

As activity increases, the rate of the heart beating increases.

Answer 1

The correct response to explain why there is an increase in the number of breaths per minute as activity increases is:

As activity increases, the oxygen needs of cells increase.

When physical activity intensifies, the body requires more energy to fuel muscle contractions. This increased energy demand leads to a higher consumption of oxygen, which in turn requires an increase in the respiratory rate to supply more oxygen to the bloodstream and remove carbon dioxide produced as a byproduct of metabolism.