During an operation, the blood supply to a small region of leg muscle is temporarily stopped. Glucose remains available from glycogen stored in the muscle.
The table shows measurements from the muscle before the blood supply is stopped and three minutes later.
| Measurement | Before blood supply is stopped | Three minutes later |
|---|---|---|
| Oxygen concentration in the muscle tissue (mg per dm³) | 6.0 | 0.0 |
| Rate of glucose use (µmol per kg per minute) | 4.0 | 12.0 |
| Rate of ATP production (µmol per kg per minute) | 120 | 24 |
Explain why ATP production continues three minutes after the blood supply is stopped. Use calculations from the table to explain why the muscle uses more glucose even though its rate of ATP production is lower.
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.