| A | B |
|---|
| active transport | energy requiring process by which substances move across the plasma membrane against a concentration gradient |
| auxin | plant hormone that moves in only one direction away from the site where it was produced and can stimulate the elongation of cells |
| gibberellins | group of plant hormones that are transported in vascular tissue and that can affect seed growth, stimulate cell division, and cause cell elongation |
| ethylene | gaseous plant hormone that affects the ripening of fruits |
| cytokinin | plant hormone that promotes cell division by stimulating production of proteins required for mitosis and cytokinesis |
| nastic response | reversible, responsive movement of a plant that occurs independent of the direction of the stimulus |
| tropism | response to an external stimulus in a specific direction |
| mesophyll | middle leaf |
