A sample of living nerve tissue is supplied continuously with glucose and oxygen. Scientists measure its oxygen uptake at rest and while it transmits repeated nerve impulses.
| Activity of nerve tissue | Oxygen uptake (cm³ per hour) |
|---|---|
| At rest | 2.2 |
| During repeated nerve impulses | 5.6 |
The repeated nerve impulses are stopped. After several minutes, the tissue returns to its resting activity.
Calculate the expected percentage decrease in oxygen uptake when the tissue returns to its resting activity.
Explain why the oxygen uptake decreases but does not fall to zero.
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.