When a plant opens and closes its stomata, it is maintaining homeostasis. Homeostasis includes the regulation of carbon dioxide and water levels necessary to perform photosynthesis. It also allows the plants to store water to prevent them from dying
The solute can move "downhill," from districts of higher to lower fixation, depending on the specificity of the protein bearer to go through the film. This procedure is called uninvolved transport or encouraged dissemination, and does not require vitality.
