Outline7 marksChallenge
The table below shows the mean stem elongation (mm) over 24 hours of etiolated pea seedlings treated with either distilled water (control) or 10⁻⁵ M auxin solution.
| Treatment | Mean stem elongation (mm) |
|---|---|
| Control | 2.5 ± 0.3 |
| Auxin | 18.0 ± 1.2 |
Outline the mechanisms of the following plant growth responses:
(a) The rapid closure of the Venus fly trap after stimulation of its trigger hairs.
(b) Auxin-induced cell elongation, making reference to the data in the table.
(c) The role of gibberellin in the germination of barley.