A student records the following results for muscle cells during exercise.
Table
| Time in minutes | Rate of oxygen use in arbitrary units | Rate of lactic acid production in arbitrary units |
|---|---|---|
| 1 | 10 | 2 |
| 2 | 15 | 5 |
| 3 | 15 | 9 |
Which explanation best accounts for the change from minute 2 to minute 3?
energy demand falls while aerobic supply remains limited, so anaerobic respiration decreases
energy demand rises while aerobic supply remains limited, so anaerobic respiration decreases
energy demand rises while aerobic supply remains limited, so anaerobic respiration increases
energy demand falls while aerobic supply remains limited, so anaerobic respiration increases
42 exam-style questions on Edexcel GCSE Biology 8.3 Respiration, covering 8.3.1 Aerobic and anaerobic respiration. Each one has a worked solution and a mark scheme showing where the marks go.