NLN PAX Practice Exam 2025 – Complete Study Guide

The process that describes water passing from a region of higher concentration to a lower concentration through a selectively permeable membrane is known as osmosis. Osmosis is a fundamental biological process that allows cells to maintain fluid balance and is vital for various physiological functions.

In osmosis, water molecules move through a selectively permeable membrane, which allows only certain molecules to pass while restricting others. This movement occurs in response to the concentration gradient of solutes; water will naturally move toward the area with a higher concentration of solutes, thereby diluting that region. This process is crucial in many biological systems, influencing how cells absorb nutrients, expel waste, and regulate internal environments.

Understanding this mechanism is vital for comprehending how cells interact with their environment and how various factors, such as solute concentration, can affect cellular health and function. Other processes mentioned, like distillation, evaporation, and sublimation, do not involve the same selective movement of water through membranes, thus making osmosis the correct choice.