in salty water the cell will lose water by osmosis.(osmosis is the movement of water from a higher water potential to a lower water potential through a selectively permeable membrane) The cell will shrink.
In fresh water where the water potencial to nside the cell is lower than the water potential outside the cell, the cell will gain water by osmosis, and its contents will become more dilute, and will propably burst, especially if its a red blood cell, or generally any human cell.(osmotic lysis)
