| A | B |
|---|
| hormone | Substance produced by one part of an organism that affects another part of the individual |
| Target Cell | Cell affected by particular hormone |
| Phototropism | Growth of a plant to a source of light |
| Auxin | substance produced in tip of seedlings that stimulates cell elongation |
| Gravitropism | Growth of a plant to the direction of gravity |
| Lateral Bud | Meristematic area on the side of a stem that gives rise to side branches |
| Herbicide | compound that is toxic to plants |
| Cytokinin | produced in growing roots; stimulate cell division & lateral bud growth |
| Gibberellin | Produce dramatic increases in size in stems & fruits |
| Ethylene | plant hormone that stimulates fruits to ripen |
| Tropism | response of a plant to an environmental stimulus |
| Thigmotropism | response of plants to touch |
| short-day plant | Plant that flowers when daylight is short |
| long-day plant | plant that flowers when days are long |
| photoperiodism | response of plants to periods of light and darkness |
| Phytochrome | plant pigment responsible for photoperiodism |
| dormancy | period of time during which a plant embryo is alive but not growing |
| abcission layer | layer of cells at the petiole that seals off a leaf from the vascular system |
| xerophyte | desert plants that can survive high heat and little water |
| epiphyte | plants that grow on the bodies of other plants |
| apical dominance | the closer a bud is to the stem, the more growth is inhibited |
