Plants in two areas of a field are the same variety and age. The table shows the results of an investigation.
Table
| Area | Soil moisture | Mineral supply | Plants with wilted leaves |
|---|---|---|---|
| P | low | adequate | 36 out of 40 |
| Q | adequate | adequate | 4 out of 40 |
Which next step would best investigate an environmental explanation for the wilting?
add more minerals in Q and compare recovery with an untreated group in Q
restore soil moisture in P and compare recovery with an untreated group in P
identify the pathogen in P from the percentage of wilted plants alone
identify the pathogen in Q from the percentage of healthy plants alone
45 exam-style questions on Edexcel GCSE Biology 5.2 Plant and body defences, covering 5.2.1 Physical plant defences, 5.2.2 Chemical plant defences, 5.2.3 Detecting plant diseases, and 5.2.4 Human physical and chemical defences. Each one has a worked solution and a mark scheme showing where the marks go.