A participant repeatedly pushes a platform with both legs. The number of pushes per minute increases throughout the test. At the end of minutes 1 and 6, the participant pushes once with maximum force.
| Time in minutes | Oxygen needed by the muscles for aerobic respiration in litres per minute | Oxygen delivered to the muscles in litres per minute | Maximum force in newtons |
|---|---|---|---|
| 1 | 1.8 | 1.8 | 640 |
| 6 | 3.0 | 2.4 | 480 |
Calculate the percentage decrease in maximum force from minute 1 to minute 6.
Explain why the maximum force was lower at minute 6. Use the oxygen data in your answer.
92 exam-style questions on AQA GCSE Biology 4.2 Respiration, covering 4.2.1 Aerobic and anaerobic respiration, 4.2.2 Response to exercise, and 4.2.3 Metabolism. Each one has a worked solution and a mark scheme showing where the marks go.