5. how did each condition affect the gradient of water potential from stem to leaf in the experimental plant. 6. what is the advantage to a plant of closed stomata when water is in short supply? 7. what are the advantages? 5. The control plant should have a normal rate of transpiration, and this transpiration in plants is controlled by the water potential. The light and wind decreases the amount of water potential in the leaves, and that through transpiration pull the water is move up to the stem, however in humidity as the water potential increases, the transpiration decreases. (www.coursehero.com) 6. When the stomata are closed the water transpiration is prevented and this can minimize the amount of water loss and can be an advantage when the water is in short supply. (www.biologyjunction.com) 7.