 Osmotic pressure is the minimum pressure which needs to be applied to a solution to prevent the inward flow of its pure solvent across this amyl permeable membrane. It is also defined as the measure of the tendency of a solution to take in pure solvent which belongs to the solution under discussion by osmosis. Potential osmotic pressure is the maximum osmotic pressure that could develop in a solution if it were separated from its pure solvent by a selectively permeable membrane. The phenomenon of osmosis arises from the propensity of a pure solvent to move through a semipermeable membrane and into its solution containing the solute to which the membrane is impermeable. This process is of vital importance in biology as the cell's membrane is semipermeable.