Osmosis
It's called osmosis.   A selectively permeable membrane will only allow certain molecules  to pass trough. To illustrate: If you have a high concentration of  sugar mole … cules on one side of the membrane, no sugar on the other  side, and the sugar molecules are too big to pass trough the  membrane. If this is the case, then water molecules will diffuse  over to the side of the membrane with a high sugar concentration.  This happens because the molecules try to distribute themselves  evenly in the solution. The water molecules move because the sugar  molecules can't. 3 people found this useful.  The rate of this movement is a function of temperature, viscosity of the fluid and the size (mass) of the particles. Diffusion explains the net flux of molecules from a region of higher concentration to one of lower concentration. Once the concentrations are equal the molecules continue to move, but since there is no concentration gradient the process of molecular diffusion has ceased and is instead governed by the process of self-diffusion, originating from the random motion of the molecules. For a more generic treatment of diffusion, see Diffusion. Diffusion from a microscopic and macroscopic point of view. Initially, there are solute molecules on the left side of a barrier (purple line) and none on the right. The barrier is removed, and the solute diffuses to fill the whole container. Once the concentrations are equal the molecules continue to move, but since there is no concentration gradient the process of molecular diffusion has ceased and is instead governed by the process of self-diffusion, originating from the random motion of the molecules. The movement of substances within the cell or across the plasma membrane is called cell transport. Mechanisms of cell transport can be divided into 2 main categories: active transport and passive transport. Both active and passive transport require energy.  In diffusion, molecules travel from a higher concentration to a lower concentration. When you put a drop of ink in a glass of water, the spreading of the ink in the water is c … alled diffusion. The function of simple  diffusion is to transfer oxygen. Facilitated diff … usion transports  water or non polar molecules. The three types of diffusion in an independent cell are simple  diffusion, facilitated, and active. The function of simple  diffusion is to transfer oxygen. Facilitated diff … usion transports  water or non polar molecules. Active diffusion transports materials  against the concentration gradient Diffusion is the net movement of molecules or atoms from a region of high concentration to a region of low concentration. In the phenomenological approach, diffusion is the movement of a substance from a region of high concentration to a region of low concentration without bulk motion. According to Fick's laws, the diffusion flux is proportional to the negative gradient of concentrations. Water, carbon dioxide, and oxygen are among the few simple molecules that can cross the cell membrane by diffusion (or a type of diffusion known as osmosis). Diffusion is one principle method of movement of substances within cells, as well as the method for essential small molecules to cross the cell membrane. In a cell, which has so many organelles and other large molecules, the water flow is generally into the cell. Animated image/movie illustrating osmosis (water is the red dots) and the selective permeability of a membrane (blue dashed line). Image from the Internet. Click on image to view movie. Answers. FACILITATED DIFFUSION. In facilitated diffusion, substances move into or out of cells down their concentration gradient through protein channels in the cell membrane. Simple diffusion and facilitated diffusion are similar in that both involve movement down the concentration gradient.  Introduction: Simple passive diffusion occurs when small molecules pass through the lipid bilayer of a cell membrane. Facilitated diffusion depends on carrier proteins imbedded in the membrane to allow specific substances to pass through, that might not be able to diffuse through the cell membrane. Simple passive diffusion. Since the net movement of diffusing molecules depends on the concentration gradient, the rate of diffusion is directly proportional to the concentration gradient (dC/dx) across the membrane.
http://www.answers.com/Q/What_function_diffuses_water_molecules https://en.wikipedia.org/wiki/Molecular_diffusion https://en.wikipedia.org/wiki/Molecular_diffusion http://www.austincc.edu/biocr/1406/labm/ex5/prelab_5_1.htm http://www.answers.com/Q/What_function_does_diffusion_have_in_the_cell http://www.answers.com/Q/What_function_does_diffusion_have_in_the_cell https://en.wikipedia.org/wiki/Diffusion http://www2.estrellamountain.edu/faculty/farabee/biobk/BioBooktransp.html http://www2.yvcc.edu/Biology/109Modules/Modules/MembraneTransport/membranetransport.htm http://www.tiem.utk.edu/~gross/bioed/webmodules/diffusion.htm
what function diffuses water molecules