| A | B |
|---|
| Chlorophyll | a green pigment found in the chloroplasts that absorbs light energy. |
| Chloroplasts | organelles in plant cells that carry out photosynthesis. |
| Dormancy | a period of time when the growth or activity of a plant or seed stops due to changes in temperature or amount of water. |
| Gravitropism | the way a plant grows or moves in response to gravity; also called geotropism. |
| Guard cells | cells located on the undersides of leaves that control when stomata open and close. |
| Hydrotropism | the way a plant grows or moves in response to water. |
| Photosynthesis | the process by which plants capture light energy and use it to make their own food. |
| Phototropism | the way a plant grows or moves in response to light. |
| Mitochondria | organelles in plant and animal cells that carry out respiration. |
| Respiration | the process by which plants and animals break down sugar to obtain energy. |
| Stomata | small openings on the underside of most leaves through which oxygen and carbon dioxide can move. |
| Thigmotropism | the way a plant grows or moves in response to touch. |
| Transpiration | the process by which plants lose water through their leaves. |
| Tropism | a plant’s response to changes in its environment. |
