A botanist monitored two groups of young sunflower plants. Both groups contained plants of the same age and had similar mean heights at the start.
| Measurement | Group P | Group Q |
|---|---|---|
| Mean height at the start in cm | 8.2 | 8.1 |
| Mean height after 21 days in cm | 24.8 | 13.4 |
| Leaves that were malformed after 21 days in % | 1 | 36 |
Using the data, describe two signs that the plants in group Q may be diseased.
The botanist concluded that the signs were caused by one particular pathogen.
Explain why the data do not support this conclusion and suggest one way the exact cause could be identified.
133 exam-style questions on AQA GCSE Biology 3.3 Plant disease, covering 3.3.1 Detection and identification of plant diseases and 3.3.2 Plant defence responses. Each one has a worked solution and a mark scheme showing where the marks go.