OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

What change occurs in blood pressure during physical exercise?

1. Blood pressure decreases

2. Blood pressure remains the same

3. Blood pressure increases

4. Blood pressure becomes irregular

The correct answer is: Blood pressure increases

During physical exercise, the body's demand for oxygen and nutrients increases as muscles work harder. To meet this demand, the heart responds by pumping blood more forcefully and more frequently. As a result, there is an increase in cardiac output, which is the volume of blood the heart pumps per minute. This increased cardiac output leads to a higher blood pressure. Additionally, exercise causes the blood vessels in the muscles to dilate to allow for better blood flow. However, the overall effect during exercise is an elevation in blood pressure due to enhanced blood flow being directed to active muscles and the increased workload on the heart. In contrast, blood pressure does not decrease or remain the same during exercise, as the body requires more efficient circulation to support physical activity. While blood pressure may fluctuate slightly as different muscle groups are engaged, it does not become irregular in a normal, healthy individual. Therefore, the correct response to how blood pressure changes during physical exercise is that it increases.