A hypertonic solution is a solution in which the concentration of solutes is higher than the concentration of the cell in the solution. Saltwater is an example of a hypertonic solution. When a cell is placed in a hypertonic solution, there will be a net flow of water out of the cell, and the cell will lose volume.

For example, if a plant cell is placed in a hypertonic solution, the water will move out of the cell, and the cell will shrink. This process is known as plasmolysis. Similarly, if an animal cell is placed in a hypertonic solution, the water will move out of the cell, and the cell will shrink. This process is known as crenation.

In contrast, a hypotonic solution is a solution that has more water outside the cell. Water then travels into the cell from the solution. When a cell is placed in a hypotonic solution, there will be a net flow of water into the cell, and the cell will gain volume.

An isotonic solution is a solution in which the concentration of solutes is the same as the concentration of the cell in the solution. If a cell is placed in an isotonic solution, there will be no net flow of water into or out of the cell, and the cells volume will remain stable.