A student investigated how light intensity affects the rate of photosynthesis in cultures of algae. The student changed the light intensity and measured the volume of oxygen produced in one hour. Carbon dioxide concentration was kept the same. The results are shown in the table.
| Light intensity (arbitrary units) | Temperature of culture (°C) | Oxygen produced in one hour (cm³) |
|---|---|---|
| 10 | 15 | 4.0 |
| 20 | 20 | 6.0 |
| 30 | 25 | 9.0 |
Explain why these results do not show the effect of light intensity alone on the rate of photosynthesis.
68 exam-style questions on AQA GCSE Biology 4.1 Photosynthesis, covering 4.1.1 Photosynthetic reaction, 4.1.2 Rate of photosynthesis, and 4.1.3 Uses of glucose from photosynthesis. Each one has a worked solution and a mark scheme showing where the marks go.