primary. Active transport is pretty straight forward, but secondary active transport a little more sophisticated, basically, the potential energy of one substances electrochemical Grady Int is exploited to move a different substance against its electrochemical Grady int. So let's think back to those pumps that we talked about a second ago. Think about those proton pumps for a moment. Now, as those proton pumps pump protons, they create electrochemical Grady int right with a high concentration of protons on one side of the membrane and a low concentration on the other. Now, in the case of the proton pumps, we just talked about this. Radiant is used to power a teepee synthesis, but it can also be utilized in different contexts. And it is in fact, utilized in different contexts to not produce eight p but to actually transport other substances. So essentially, um, as the protons build up on one side, they're allowed to move back down, their concentration radiant against the direction of the pump. And as they do this, the energy released as they move down their concentration. Grady int is used to bring another substance against its own concentration ingredient. Or, I should say, electrochemical, radiant because it has both a concentration and it can have a new electrical component as well. Anyways, um, this action actually can come in a variety of flavors. For example, So Eun, importers on Lee move one salute in one direction and their Onley using a new electrical radiant. So essentially, um, you'd have an electrical radiant created by some pump using primary active transport And that electrical radiant will allow some substance to move against its concentration ingredient because of this electrical radiant. So that is a unit port. Ah, Sim porters will move both salutes in the same direction. So in this case, uh, let's say for all of these a is the salute moving against its concentration. Radiant. Right, So outside, here's we're gonna have low a and hence we're on. I should say this side. Who knows what outsider inside is in this diagram left high A. So a is moving against its concentration, radiant in all these images, right, it's moving from low to high. So in the case of the unit Porter, it is moving from low to high due to an electrical Grady int created by some pump that is driving a in that direction, Sim Porter will move a and some other Saul, you'd be in the same direction. And in this case, B is going to be moving down. It's electrochemical, Grady int, whereas A is moving against its electro chemical radiant in the case. And I'm sorry, this is a simp order. In the case of anti porters, the two solid it's will actually move in opposite directions. So this is an anti port, and in this case, B is moving down, its concentration radiant. And A is moving against its concentration ingredient. So these air the three forms that you'll find secondary active transport in now. Specifically, supporters and anti porters make up something called co transport, which is when, um that I'm sorry.