The Sodium-Potassium Pump

Vocabulary flashcards covering the structure, function, and mechanism of the sodium-potassium pump in animal cells and neurons.

Sodium-potassium pump

A large membrane-associated enzyme and protein pump found in the cell membrane of all animal cells that transports sodium ions out and potassium ions into the cell to stabilize cell membrane potential

Adenosine triphosphate (ATP)

The energy source (cycle) used by the sodium-potassium pump to transport ions across the cell membrane.

Action potential

The basis of electrical signaling in neurons, which requires the stabilization of the cell’s membrane potential by the sodium-potassium pump.

Phosphate group

A chemical group transferred from ATP to the pump that prompts a conformational change, causing sodium ions to be released into the extracellular fluid.

Conformational change

A change in the shape of the pump prompted by the transfer of a phosphate group or the binding of ions to move them across the membrane.

Ion movement ratio

The specific count in each cycle where the pump moves $3$ sodium ions out of the cell and $2$ potassium ions into the cell.

Resting membrane potential effect

The net loss of positive ions during the pump cycle that makes the electrical charge of the cell slightly more negative.

Extracellular fluid

The area outside the cell into which the pump releases sodium ions after a conformational change.