Diffusion and Osmosis

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Osmosis is a passive movement of water through a selectively permeable membrane moves from an area of higher concentration to an area of lower concentration. In this lab, we can determine the direction of diffusion of small molecules by measuring the diffusion of small molecules through dialysis tubing. This tubing acts as a selectively permeable membrane, and allow to pass larger molecules slowly.

Introduction:
Cells have kinetic energy and it causes the molecules of the cell to move around and bump into each other. Diffusion is one result of this molecular movement. Diffusion is the passive movement of molecules from an area of higher concentration to lower concentration. Osmosis is a passive movement of water through a selectively permeable membrane moves from an area of higher concentration to an area of lower concentration. Diffusion or osmosis occurs until dynamic equilibrium has been reached. This is the point where the concentrations in both areas are equal and no net movement will occur from one area to another. If two solutions have the same solute concentration, the solutions are said to be isotonic. If the solutions differ in concentration, the area with the higher solute concentration is hypertonic and the area with the lower solute concentration is hypotonic. Since a hypotonic solution contains a higher level of solute, it has a high solute potential and low water potential. This is because water potential and solute potential are inversely proportional. A hypotonic solution would have a high water potential and a low solute potential. An isotonic solution would have equal solute and water potentials. Water potential is composed of two main things, a physical pressure component, and pressure potential. Water will always move from areas of high water potential to areas of low water potential. This experiment will prove that diffusion and osmosis occur between solutions of different concentrations until dynamic equilibrium is reached, affecting...
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