Animation - Sodium-Potassium Exchange Pump

What is the purpose of pumping sodium and potassium across a membrane?

The sodium potassium pump is a well understood example of active transport. Sodium and potassium ions are pumped in opposite directions across the membrane building up a chemical and electrical gradient for each. These gradients can be used to drive other transport processes. In nerve cells the pump is used to generate gradients of both sodium and potassium ions. These gradients are used to propagate electrical signals that travel along nerves. Therefore the action of nervous tissue requires ATP to generate resting potentials. Poisons that disable the pump prevent proper functioning of the nervous system.

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