Secondary active transport, or coupled transport, does not use ATP directly. Instead, it hitches a ride on the energy stored in an electrochemical gradient created by primary active transport. How it Works
Found in nearly all animal cells, this pump is the gold standard of primary active transport. It uses one ATP molecule to export three sodium ions ( Na+cap N a raised to the positive power ) out of the cell and import two potassium ions ( K+cap K raised to the positive power Secondary active transport, or coupled transport, does not
Na+/K+cap N a raised to the positive power / cap K raised to the positive power Secondary active transport