| 1. | It is caused by an electrical signal. |
| 2. | One chemical involved is ethylene. |
| 3. | Auxin causes a growth increase on one side of the stem. |
| 4. | Auxin causes a decrease in growth on the side of the stem exposed to light. |
| 1. | They only act by altering gene expression |
| 2. | They often have a multiplicity of effects |
| 3. | They function independently of other hormones. |
| 4. | They directly control plant protein synthesis and assembly. |
| 1. | light causes auxin to accumulate on the shaded side of a plant stem. |
| 2. | auxin indirectly inhibits elongation of plant stem cells |
| 3. | auxin is produced by the apical meristem of the coleoptile and moves downward. |
| 4. | all hormones move downward via the xylem. |
| List I | List II |
| A. Indole Acetic Acid | I. Increase length of grapes stalks |
| B. Zeatin | II. Hastens fruit ripening in tomatoes |
| C. Gibberellic acid | III. Overcome apical dominance |
| D. Ethephon | IV. Rooting in stem cuttings |
| 1. | A-II, B-I, C-IV, D-III |
| 2. | A-IV, B-II, C-I, D-III |
| 3. | A-IV, B-III, C-I, D-II |
| 4. | A-III, B-IV, C-II, D-I |
| 1. | Auxin | 2. | Cytokinin |
| 3. | Ethylene | 4. | Abscisic acid |