| A | B |
|---|
| plant hormones | a substance that is produced in one part of an organism and affects another part of the same individual |
| target cell | The portion of an organism affected by a particular hormone |
| receptor | part of the target cell to which a hormone binds |
| auxins | stimulate cell elongation in response to light |
| phototropism | a plant's response to light |
| herbicides | compounds which are toxic to plants |
| cytokinins | inhibit cell elongation and stimulate cell division |
| giberellins | increase size of stems and fruit |
| ethylene | causes fruit to ripen |
| tropism | the response of a plant to external stimuli |
| gravitropism | response which causes roots to grow down and stems to grow up |
| thigmotropism | a plant's response to touch |
| rapid response | response not associated with growth |
| photoperiodism | response to periods of light and darkness |
| short-day plants | grow when days are shorter due to seasons |
| long-day plants | grow when days are longer due to seasons |
