Students investigate a plant's distribution. They measure soil conditions at four sites.
| Site | Soil pH | Soil moisture / arbitrary units | Mean number of plants |
|---|---|---|---|
| W | 4 | 20 | 3 |
| X | 4 | 60 | 15 |
| Y | 7 | 20 | 18 |
| Z | 7 | 60 | 30 |
Which comparison provides evidence for a moisture effect without changing pH, and which conclusion does it support?
W with X; plant abundance is higher in wetter soil.
W with Y; plant abundance is higher in wetter soil.
X with Y; plant abundance is higher in drier soil.
Y with Z; plant abundance is higher in drier soil.
40 exam-style questions on AQA GCSE Biology 7.1 Adaptations, interdependence and competition, covering 7.1.1 Communities, 7.1.2 Abiotic factors, 7.1.3 Biotic factors, and 7.1.4 Adaptations. Each one has a worked solution and a mark scheme showing where the marks go.