The table shows four possible methods for investigating light intensity and photosynthesis.
Table
| Method | Lamp distance | Water temperature | Pondweed shoot |
|---|---|---|---|
| W | changed | kept constant | same shoot |
| X | changed | allowed to rise | same shoot |
| Y | kept constant | changed | same shoot |
| Z | changed | kept constant | different lengths |
Which method allows the student to relate a change in gas production to light intensity alone?
method W
method X
method Y
method Z
44 exam-style questions on Edexcel GCSE Biology 6.1 Photosynthesis, covering 6.1.1 Photosynthetic organisms as producers, 6.1.2a Limiting factors on the rate of photosynthesis, 6.1.2b Interactions of limiting factors on photosynthesis, and 6.1.3 Inverse square law and light intensity. Each one has a worked solution and a mark scheme showing where the marks go.