A researcher grows two cultures. One culture contains mammalian skeletal-muscle cells and the other contains yeast cells. Both cultures are supplied with glucose and initially have enough oxygen for aerobic respiration.
Oxygen is removed from both cultures. The concentrations of lactic acid and ethanol are measured immediately and after 8 minutes.
| substance | culture P at 0 minutes (mmol dm⁻³) | culture P at 8 minutes (mmol dm⁻³) | culture Q at 0 minutes (mmol dm⁻³) | culture Q at 8 minutes (mmol dm⁻³) |
|---|---|---|---|---|
| lactic acid | 0.3 | 5.1 | 0.0 | 0.0 |
| ethanol | 0.0 | 0.0 | 0.2 | 4.6 |
Explain which culture contains the mammalian skeletal-muscle cells and which culture contains the yeast cells. Include the type of respiration and where it takes place in the cells.
The skeletal-muscle cells must maintain the same rate of ATP supply after the oxygen is removed.
Explain how their rate of glucose use will change.
98 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.