3. when a person is given fluid intravenously (an i. v.) in the hospital, the fluid is typically a saline solution balanced — with the correct amount of dissolved materials — to human body tissues. explain why this is necessary.

In an isotonic solution the cytoplasm and ECM are balanced so they cell may not become hypotonic nor hypertonic. You want an equal amount of fluid inside a cell and the same outside to reach a equilibrium otherwise your blood cell for example would shrink or swell and burst.

I.V. fluid is given to pt's. in order to keep them hydrated and prevents dehydration especially if they cannot eat. Dehydration is a life threatnening emergency

Dextrose is also given I.V. in a sense is sugar + saline solution and is very helpful on diabetics. If a diabetic were not eating in the hospital setting you would give dextrose to help keep the body hydrated and the sugar level from falling too low.

Hope this helps!!