Summary:
- Active transport is the energy-requiring process of pumping molecules and ions across membranes "uphill" - against a concentration gradient.
- To move these molecules against their concentration gradient, a carrier protein is needed.
- The sodium-potassium pump is an active transport pump that exchanges sodium ions for potassium ions.
- The pump is found in the plasma membrane of almost every human cell and is common to all cellular life.
- It helps maintain cell potential and regulates cellular volume.
- It is also important for the conduction of electrical impulses along nerve cells.