You are looking at a muscle cell and analyzing the events th…

You are looking at a muscle cell and analyzing the events that lead to muscle contraction. You find that there is a pump called the sodium potassium ATPase that will pump potassium into cells while also pumping sodium out of cells both against their concentration gradients. You think for a second and realize that this process is very similar to one of the processes you have studied. Which of the following is most similar to this process?