Osmosis

Tendency of fluids (e.g., water) to move from the less concentrated to the more concentrated side of a semipermeable membrane.

The passage of water through a semipermeable membrane, from a region of low concentration of solutes to one of higher concentration. Reverse osmosis is the passage of water from a more concentrated to a less concentrated solution through a semi-permeable membrane by the application of pressure.

Bulk flow of water through a semipermeable (or more accurately, differentially permeable) membrane into another (aqueous) phase containing more of a solute (dissolved compound). As an example, let us set up an osmotically active system. There are two solutions, A and B. Solution A has less salt dissolved in it than solution B and, furthermore, the two solutions are separated by a differentially permeable membrane (this looks like a plastic film). Water molecules (and only water molecules) will flow from solution A through the membrane and into solution B. The reason for this is that the membrane allows free passage only to water molecules. The bulk flow of water has the effect of diluting solution B, while concentrating solution A. Water will flow from region A to region B until the salt concentrations of both solutions are equal. Osmosis is therefore a process in which water passes from regions of low salt concentration to regions of high salt concentration. The process can be viewed as equalizing the number of water and solute molecules on both sides of the membrane.

The movement of a liquid through a semipermeable membrane from a less dense to greater density medium.

The movement of a solvent from one part of the body through a semipermeable membrane to another part where there is a higher concentration of molecules.

The passage of solvents across a membrane so as to equalize the concentrations of solutes on each side of the membrane.

Movement of a solvent through a membrane from a place of higher concentration to a place of lower concentration until the concentrations on both sides equalize.

The process by which fluid passes across a permeable membrane from a solution of lesser to a solution of greater concentration.

The passage of a solvent from a less concentrated to a more concentrated solution through a ‘semipermeable membrane. This tends to equalize the concentrations of the two solutions. In living organisms the solvent is water and cell membranes function as semipermeable membranes, and the process of osmosis plays an important role in controlling the distribution of water. The osmotic pressure of a solution is the pressure by which water is drawn into it through the semipermeable membrane; the more concentrated the solution (i.e. the more solute molecules it contains), the greater its osmotic pressure.

The passage of fluids through a separating, semipermeable membrane, so as to become mixed with one another. Osmotic pressure is a term applied to the tendency of a fluid to do this, and depends largely upon the amount of solid which it holds in solution.

The passage of solvent through a semipermeable membrane that separates solutions of different concentrations. The solvent, usually water, passes through the membrane from the region of lower concentration of solute to that of a higher concentration of solute, thus tending to equalize the concentrations of the two solutions. The rate of osmosis is dependent primarily upon the difference in osmotic pressures of the solutions on the two sides of a membrane, the permeability of the membrane, and the electric potential across the membrane and the charge upon the walls of the pores in it.

The transportation of aqueous particles over a partially penetrable barricade, shifting from an expanse of superior aqueous potential (inferior solute density) to an area of inferior aqueous potential (superior solute density).

The transfer of aqueous particles through a semi-permeable barrier, selectively allowing the passage of water, from a domain of considerable aqueous propensity (low solute saturation) to an expanse of inferior aqueous potential (high solute concentration), is known as osmosis.

The process by which water, or any other solvent, moves through a semipermeable membrane from a region of lower solute concentration to a region of higher solute concentration.