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Water is the solvent which is primarily used in the human bodies as well as in the bodies of other living things. The primary reason why water is used in this sense is that it is a universal solvent. In the bodies of living organisms, some of the solutes which use water as a solvent are Sodium chloride, Potassium Ions, Calcium Ions and other minerals and ionic compounds. Water being their solvent makes it easier for them to be transported from one location to another, for instance Potassium and Sodium ions transport to the neurons.
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