|MadSci Network: Cell Biology|
Actually, the human cell does participate in actions involving the uptake and secretion of water. However, this is done to help regulate cell volume (Regulating cell volume is actually the necessary process of maintaining salt levels in and around the cell). Cells don't actually use water for nourishment just to be excreted as a waste product. More accurately, water is allowed into a cell, and excess water is removed from the cell due to a process called osmosis. What is this process? When higher concentrations of salt exist inside of a cell or decreased salt concentrations exists outside of the cell - Water is caused to enter into the cell. Excess water and salt are removed from the cell through channels that are activated by the cell. This regulation of salt is essential for the cells' optimal performance. Were it not for this process (collectively known as OSMOREGULATION)cells would shrink or bust. Thus, in answer to the other part of your question, the water that is initially taken in is not necessarily the same water that is present at cellular death. For additional information on the newest info on osmosis please see WWW.MEDICALNEWSTODAY.COM
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