In an isotonic solution, what happens to the cell?

• A. The cell bursts
• B. The cell shrinks
• C. The cell neither gains nor loses water
• D. The cell absorbs excess solute

Answer: (C)

In an isotonic solution, the concentration of solutes outside the cell is equal to the concentration of solutes inside the cell. This balance means that there is no net movement of water across the cell membrane. Water molecules move in and out of the cell at equal rates, resulting in no change in the cell's size or shape.

When a cell is placed in an isotonic environment, it maintains homeostasis, which is essential for cellular function. This environment allows the cell to remain stable without the stress of either swelling due to excess water intake or shrinking due to the loss of water.

The other options describe situations that occur in different types of solutions. For instance, in a hypotonic solution, the cell would absorb water and possibly burst, while in a hypertonic solution, the cell would lose water and shrink. Therefore, the correct description of a cell's behavior in an isotonic solution is that it neither gains nor loses water.