Students investigated the effect of light intensity on the rate of photosynthesis by varying the distance of a lamp from a piece of pondweed. They measured the rate of photosynthesis by counting the number of oxygen bubbles produced per minute. Table 1 shows their results.
| Distance of lamp in cm | Test 1 | Test 2 | Test 3 | Mean |
|---|---|---|---|---|
| 10 | 61 | 65 | 63 | AAA |
| 20 | 41 | 43 | 42 | 42.0 |
| 30 | 25 | 24 | 26 | 25.0 |
| 40 | 12 | 31 | 14 | 13.0 |
| 50 | 6 | 7 | 5 | 6.0 |
Calculate the mean value AAA.
Identify the anomalous result in Table 1 at a distance of 40 cm.
Explain how the students used the results in Table 1 to calculate the mean value of 13.0 for the distance of 40 cm.
54 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.