Here is the breakdown of the two systems. The Energy Source: It uses energy directly from a chemical reaction, typically the hydrolysis of ATP (adenosine triphosphate).
A membrane protein acts as a pump. It binds to a molecule on one side of the membrane, breaks an ATP molecule to release energy, changes shape, and releases the molecule on the other side. Here is the breakdown of the two systems
A membrane protein (co-transporter) couples the movement of one molecule down its gradient (releasing energy) with the movement of a different molecule against its gradient (using that energy). It binds to a molecule on one side
Cells must constantly move molecules against their concentration gradient (from low to high concentration). This process requires energy and is called active transport . However, not all active transport is the same. The key distinction lies in where that energy comes from . This process requires energy and is called active transport