And this is analogous to basically moving this marker from a low potential to a high potential. So this marker will never, by itself spontaneously move from a low to high potential. To actually get it to move from here to here, I have to take this mark or move it along this line. So I have to apply force, I have to move this and do works, I have to transfer energy. And in the same exact way, these membrane pumps utilize energy to move these ions and molecules against their electrochemical gradient from a low to a high potential. And because they use energy, we call them active transporters.