Final answer:
The NaK pump is also named an ion pump, which functions to move sodium and potassium ions against their concentration gradients through a process involving ATP hydrolysis and phosphorylation of the pump. Option 1 is correct..
Step-by-step explanation:
Beside it being an ATP driven pump, the NaK pump is also named an ion pump. This term reflects its function in moving ions -- specifically sodium ions (Na+) out of the cell, and potassium ions (K+) into the cell, against their respective concentration gradients. The Na+/K+ ATPase, as it is scientifically known, is crucial in maintaining the electrochemical gradient of cells, and operates through a consistent cycle that involves the hydrolysis of ATP and respective phosphorylation and dephosphorylation of the pump, resulting in the translocation of the ions.
The process begins with three sodium ions inside the cell binding to the pump, which then hydrolyzes ATP and undergoes a conformational change that releases the sodium ions outside. Subsequently, two potassium ions from outside bind to the protein, which after dephosphorylation, returns to its original shape and transports the potassium ions inside the cell, completing the cycle. This primary active transport mechanism is essential for numerous cellular functions, including nerve impulse transmission and muscle contraction.