A sodium-potassium antiport maintains the extracellular concentration of sodium at levels that are about 20–30 times higher than inside the cells. What directly supplies the energy for maintaining this gradient? g

a sodium-potassium antiporter maintains the concentration gradient with help of direct supply of energy by the hydrolysis of ATP. ATP hydrolysis involves Na+/K+-ATPase  enzyme.

during active transport, energy is needed because, it transports substances from higher concentration to lower concentration.

ATP is also needed in the binding and releasing of sodium or potassium ions in those pumps and due to that conformational changes in the protein happens.

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