The movement of molecules, specifically water and any solutes, is vital to understand in light of plant processes. This will be more or less a quick review of several guiding principles of water motion in reference to plants.
Diffusion is the movement of a substance from an area of high concentration to an area of low concentration. Diffusion happens in liquids and gases because their particles move randomly from place to place. Diffusion is an important process for living things; it is how substances move in and out of cells
