What does it mean if a solution is hypertonic?

A hypertonic solution is defined by having a higher concentration of solutes outside the cell compared to the concentration of solutes inside the cell. This difference in concentration causes water to move out of the cell in an attempt to balance the solute concentrations on both sides of the cell membrane. As a result, the cell may shrink or crenate due to the loss of water.

In contrast, options that describe the concentration being lower or equal, such as less concentration outside compared to inside or equal concentration, refer to hypotonic and isotonic solutions, respectively. A hypotonic solution causes water to move into the cell, potentially leading to swelling, while an isotonic solution maintains equilibrium, ensuring no net movement of water occurs. Thus, the definition of hypertonic directly aligns with having a higher concentration of solutes outside the cell.