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Heather and Mariah

 

We think that the change in the cells occurs from the diffusion of water across the cell membrane and into or out of the cell. When the cell is in a .1% salt solution, the membrane is filled with water. When this is replaced with the 25% salt solution, the water wants to move to the area with more salt so that it is reduced to the same concentration as within the cell.  Brownian motion explains why this water is in motion and thus able to pass out of the cell. When the distilled water is introduced, the water wants to move back into the cell and so the membrane fills back up with water and the equilibrium between the cell and its surrounding water is restored. We think an additional way to test this idea would be to measure the amount of salt present within the cell while it is immersed in different solutions and see if there is a connection between what the cell looks like and how similar or different its salt level is to that of the surrounding solution.