Example !!install!! — Primary Active Transport

-ATPase): Found in the lining of the stomach, these pumps move hydrogen ions into the stomach lumen to create the highly acidic environment necessary for digestion. Calcium Pumps ( Ca2+cap C a raised to the 2 plus power

This energy causes the pump to change its shape, opening toward the outside of the cell and releasing the three Na+cap N a raised to the positive power Potassium Binding: Two potassium ions ( K+cap K raised to the positive power ) from outside the cell bind to the pump. Dephosphorylation: The binding of K+cap K raised to the positive power triggers the release of the phosphate group. primary active transport example

Na+/K+cap N a raised to the positive power / cap K raised to the positive power -ATPase): Found in the lining of the stomach,

In scientific terms, this is a transmembrane protein called the Na+/K+ ATPase. But let's visualize him as a burly, tireless guard standing at the city gate. He has a specific job that defies the laws of nature. He must kick the Sodium army out and pull the Potassium citizens in , fighting against the flow of nature every second of the day. Na+/K+cap N a raised to the positive power

The "uphill" gradient created by primary transport is often used as a "downhill" energy source for other molecules (like glucose) to hitch a ride into the cell. Summary Table Primary Active Transport Energy Source Direct hydrolysis of ATP Direction Against the concentration gradient (Low to High) Main Protein Type Pumping proteins (ATPases) Key Example Sodium-Potassium Pump (