Osmosis in Plants


Plant Osmosis

Diffusion is the movement of molecules from an area of higher concentration to that of a lower concentration. Once there are the same number of molecules on both sides, there is no longer any net movement because a gradient no longer exists. Osmosis is a special case of diffusion. Osmosis is the movement of water through a selectively permeable membrane from a region of higher water concentration to a region of lower water concentration. Adding particles to one side of a membrane can establish a concentration gradient for water. The increase in particles on one side results in a decrease in water for that area.


Plant cells have a cell wall as well as a plasma membrane. The cell wall is a strong and rigid structure that is used by the cell to create osmotic pressure within the cell. This pressure can build because of the rigidity of the cell wall. The cells within a plant that contain high water pressure act as the plant supportive structure, helping to give it its shape. If particles are added to the plant then the osmotic pressure would decrease which causes the supportive structure of the plant diminish and the plant becomes limp and shriveled