When a cell is in a hypertonic solution, what occurs to its internal water concentration?

In a hypertonic solution, the external environment has a higher concentration of solutes compared to the inside of the cell. This difference in solute concentration causes water to move out of the cell in an attempt to equalize solute concentrations on both sides of the cell membrane. As water leaves the cell, the internal water concentration decreases.

This process, known as osmosis, is driven by the principle that water moves from areas of lower solute concentration (where there is a higher concentration of water) to areas of higher solute concentration (where there is a lower concentration of water). Consequently, as water exits the cell to balance the solute concentrations, the internal concentration of water diminishes, confirming that the correct answer is a decrease in internal water concentration.