A researcher compared two varieties of shrub that were identical except that variety P had thorns and variety Q did not have thorns. Rabbits were allowed to feed on the shrubs for the same length of time.
| Shrub variety | Mean mass of shoots eaten in g |
|---|---|
| P | 27.3 |
| Q | 78.0 |
Use the mean mass for variety Q as the original value. Calculate the percentage reduction in feeding shown by the result for variety P.
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.