A scientist investigated how a bacterial plant pathogen enters leaves.
The same number of bacteria was placed on each of 100 leaves in each group. A waterproof coating was used to seal the stomata. The coating did not kill the bacteria or damage the leaves. All other conditions were kept the same.
| Treatment of leaves | Leaves infected after 7 days (%) |
|---|---|
| Cuticle intact; stomata not sealed | 26 |
| Cuticle intact; stomata sealed | 4 |
| Small openings made through cuticle; stomata sealed | 61 |
Explain which type of plant defence the waxy cuticle provides. Use the results in the table in your answer.
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.