Primary Active Transport And Secondary Active Transport 【Limited Time】

Active transport is the movement of molecules across a cell membrane against their electrochemical gradient (from low to high concentration). This process requires energy because it is moving substances "uphill." The key distinction between the two main types lies in the direct source of that energy. 1. Primary Active Transport Definition: Primary active transport directly uses chemical energy (typically from the hydrolysis of ATP) to power the transport of molecules across the membrane.