The Na+/K+ ATPase pump plays only a minor role in directly generating the restin

the pump operates to expel the na+ that is constantly entering through other transporters and ion channels. In this way, the pump keeps the na+ concentration in the cytosol about 10-30 times lower than in the extracellular fluid and the K+ concentration about 10-30 times higher. under normal conditions, the interior of most cells is at a negative electric potential compared with the exterior, so that positive ions tend to be pulled into the cell. This means that the inward electrochemical driving force for Na+ is large, as it includes the driving force due to the concentration gradient and a driving force in the same direction due to the voltage gradient. 

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