Osmosis+and+diffusion

Stephanie Gutierrez Period 2.
 * a. Students know ****cells are enclosed within semipermeable membranes that regulate their interaction with their surroundings.

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If two solutions of different concentration are separated by a semi-permeable membrane which is permeable to to the smaller solvent molecules but not to the larger solute molecules, then the solvent will tend to [|diffuse] across the membrane from the less concentrated to the more concentrated solution. This process is called osmosis. Osmosis is of great importance in biological processes where the solvent is water. The transport of water and other molecules across biological [|membranes] is essential to many processes in living organisms. The energy which drives the process is usually discussed in terms of[|osmotic pressure]. ||
 * =Osmosis=

|| =Diffusion= Diffusion refers to the process by which molecules intermingle as a result of their[|kinetic energy] of random motion. Consider two containers of gas A and B separated by a partition. The molecules of both gases are in constant motion and make numerous collisions with the partition. If the partition is removed as in the lower illustration, the gases will mix because of the [|random velocities] of their molecules. In time a uniform mixture of A and B molecules will be produced in the container. The tendency toward diffusion is very strong even at room temperature because of the high molecular velocities associated with the [|thermal energy] of the particles. || ||