Living cells depend on a precise balance of water and solutes. which term describes the control of the gain or loss of water and dissolved solutes, such as the ions of nacl and other salts.

The term in question is referred to as osmoregulation.
Since water and its soluted metabolites are key to the survival and normal function of the cell, there are many membrane proteins that regulate the exchange of water, ions and other osmolites between the cell and its surroundings. 

True to the fact it is actually false