A solution that has an equal concentration of solute and solvent is termed an isotonic solution. In this scenario, the osmotic pressure is balanced, allowing for the free movement of water across the cell membrane without causing any significant change in cell volume or pressure. Isotonic solutions are crucial in biological systems, particularly in maintaining cellular homeostasis and in medical treatments such as intravenous fluid administration. The concentration of solutes outside the cell matches that of the inside, preventing cell swelling or shrinking, which could otherwise disrupt cellular function.