A student measures the volume of oxygen produced by algal cultures in one hour at different light intensities. The temperature is kept constant. The results are shown in the table.
| Light intensity (lux) | Oxygen produced at 0.04% carbon dioxide (cm³ per hour) | Oxygen produced at 0.4% carbon dioxide (cm³ per hour) |
|---|---|---|
| 2 000 | 2 | 2 |
| 5 000 | 7 | 7 |
| 10 000 | 7 | 16 |
Which conclusion about the limiting factors at 0.04% carbon dioxide is supported for the cultures at 2 000 lux and 10 000 lux?
Carbon dioxide is limiting at 2 000 lux and at 10 000 lux.
Light is limiting at 2 000 lux, but carbon dioxide is limiting at 10 000 lux.
Carbon dioxide is limiting at 2 000 lux, but light is limiting at 10 000 lux.
Light is limiting at 2 000 lux and at 10 000 lux.
117 exam-style questions on OCR GCSE Biology 1.4 Photosynthesis, covering 1.4.1 Photosynthesisers as biomass producers, 1.4.2 Factors affecting the rate of photosynthesis, and 1.4.3 Limiting factors in photosynthesis. Each one has a worked solution and a mark scheme showing where the marks go.