What does the term "hypertonic" refer to regarding solutions?

The term "hypertonic" refers specifically to a solution that has a higher concentration of solutes in comparison to another solution. In biological terms, this is often discussed in the context of cell environments. When a cell is placed in a hypertonic solution, water moves out of the cell toward the area of higher solute concentration, leading to cell shrinkage or crenation. This concept is vital in understanding fluid and electrolyte balance in the body, as it affects how cells interact with their surrounding solutions.

In contrast, a lower concentration of solutes would refer to a hypotonic solution, while equal concentrations characterize an isotonic solution. A solution with no solutes present would not have any osmotic effect on cells and is not relevant when discussing tonicity. Thus, recognizing the definition of hypertonic is crucial for understanding osmotic pressure and the movement of fluids in and out of cells.