What is osmosis:

What is Osmosis ? The one definition of osmosis is 'The movement of water from a high concentration to a low concentration, down it's concentration gradient, across a partially permible membrane, until osmotic pressue is equal'. Why would the mass of a piece of potato change when it is placed in different sugar solutions? It's all due to a process called osmosis and the movement of water from a high water potential to a place of low water potential, passing through a partially permeable membrane. So what does this mean? What are the differences and similarities between osmosis , active transport and diffusion? Osmosis is a term used to describe the movement of water molecules from a high water potential to a low water potential. In summary, the loop of Henle is surrounded by tissue fluid which has a high concentration of ions in it. This causes water to move out of the descending limb by osmosis . This produces a more concentrated filtrate because of this, ions move out of the loop in the thin ascending limb.