In active transport, molecules move against a concentration gradient, therefore

In active transport, molecules move from a region of low concentration to a region of high concentration. This is against the natural tendency of molecules to move from a region of high concentration to a region of low concentration, which is known as the concentration gradient. Active transport requires the use of energy to transport molecules across a cell membrane, such as through the use of specialized proteins or pumps. Therefore, active transport is essential for maintaining the proper balance of molecules inside and outside of cells.