Final answer:
When cells are placed in a hypertonic solution, they lose water, causing the cells to shrivel in a process known as crenation. This occurs through osmosis, the diffusion of water across a semipermeable membrane from higher to lower water concentration.
Step-by-step explanation:
When cells are placed in a hypertonic solution, they lose water and shrivel, and this process is called crenation. The correct term for the process where water moves across a semipermeable membrane is osmosis. Osmosis describes the diffusion of water from an area of higher water concentration to an area of lower water concentration. When a cell is placed in a solution that has a higher solute concentration (hypertonic), water moves out of the cell, causing the cell to shrink, or crenate. This is often contrasted with a hypotonic solution, where the water would move into the cell, potentially causing it to swell and burst. An isotonic solution is one where the solute concentration is the same both inside and outside of the cell, resulting in no net movement of water.