Diffusion And Osmosis

Diffusion is the flow of events / migration of a substance in the solvent from the high concentration to low concentration part. A simple example is the provision of sugar to the liquid fresh tea.Gradually, the liquid becomes sweeter. Another example is water vapor from the kettle that diffuses in the air.

Osmosis is the movement of water through a selectively permeable membrane from the more dilute to the more concentrated. Semipermeable membrane must be penetrated by the solvent, but not by the solute, resulting in the pressure gradient along the membrane. Osmosis is a natural phenomenon, but can be artificially inhibited by increasing pressure on parts with dense concentrations exceeding the concentration becomes more dilute.Force per unit area required to prevent the flow of solvent through a selectively permeable membrane and enter the solution with a more dense concentration is proportional to the turgor pressure.Osmotic pressure is a colligative properties, which means that these properties depend on the concentration of solute, and not on the nature of the solute itself.

Osmosis is an important topic in biology because of this phenomenon may explain why the water can be transported into and out of cells. 
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