Solutions that have a higher solute concentration than the insides of a cell are referred to as hypertonic solutions. When a cell is placed in a hypertonic solution, water will move out of the cell in an attempt to balance the solute concentrations on both sides of the cell membrane.
This movement of water can cause the cell to shrink or undergo a process known as crenation. Essentially, the hypertonic solution pulls water out of the cell because the solute concentration is greater outside than inside, leading to a net movement of water from an area of low solute concentration (inside the cell) to an area of high solute concentration (the surrounding solution).
Understanding hypertonic solutions is crucial in various biological and medical contexts, such as in the administration of IV fluids where it’s important to know how different solutions will affect cell volume and health.