A volunteer completed repeated step-ups for 3 minutes. A researcher measured the volunteer's blood lactic acid concentration.
| Time of measurement | Blood lactic acid concentration in mmol per dm³ |
|---|---|
| Before the step-ups | 1.2 |
| Immediately after the step-ups | 8.6 |
Which inference is best supported?
The volunteer's oxygen uptake should return immediately to the resting rate because the exercise has stopped.
The volunteer's oxygen uptake should remain high because ethanol must be removed from the muscles.
The volunteer's oxygen uptake should fall below the resting rate until the lactic acid has been stored.
The volunteer's oxygen uptake should remain above the resting rate for a time after the step-ups.
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.