Which process do cells use to transport substances from a region of lower concentration to a region of higher concentration?

Cells use active transport to move substances from an area of lower concentration to an area of higher concentration. This process is essential for maintaining the proper concentrations of ions and nutrients inside the cell, which is critical for various cellular functions.

Active transport requires energy, often in the form of ATP, because it is working against the natural flow of diffusion, which tends to move substances from high to low concentration. Through active transport mechanisms, such as pumps or specialized transport proteins in the cell membrane, cells can absorb necessary substances even when these substances are less concentrated outside the cell.

This process is crucial in many biological systems, such as in nerve cells where sodium and potassium ions must be maintained at specific concentrations to facilitate signal transmission. By utilizing active transport, cells can regulate their internal environment effectively.