A young shoot is placed horizontally in a chamber. The only light enters from directly above.
The table shows the distribution of auxin in the growing region of the shoot before any curvature is visible.
| Side of shoot | Proportion of auxin in the growing region (%) |
|---|---|
| upper | 38 |
| lower | 62 |
Explain how the direction of the light and the position of the shoot cause the auxin distribution shown, and predict the direction in which the shoot will grow.
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.