A fruit-storage team investigates whether ethene affects the ripening of plums. Equal batches of unripe plums of the same variety are placed in five identical chambers. The temperature and storage time are the same for every chamber.
| Chamber treatment |
|---|
| Air with ethene added, circulated |
| Air only, circulated |
| Air only, not circulated |
| Nitrogen only, circulated |
| Air with twice as much ethene added, circulated |
Which chamber should be used as the control for the chamber given air with ethene added, circulated?
the chamber with nitrogen only, circulated
the chamber with twice as much ethene, circulated
the chamber with air only, not circulated
the chamber with air only, circulated
105 exam-style questions on Edexcel GCSE Biology 6.3 Plant hormones, covering 6.3.1 Plant hormones and tropisms and 6.3.2 Commercial uses of plant hormones. Each one has a worked solution and a mark scheme showing where the marks go.