 collecting duct and distal convoluted tubule. I'm not going to say much. And the reason why I'm not going to say much is because we're actually going to spend another whole lecture talking about the thing that can happen in distal convoluted tubule and collecting duct. The take home that I want you to have right now is that filtrate can enter this zone as low as 100 millios moles. What that means is that that's super dilute. That's actually like, if you peed that out, you would be like, dude, did I even pee? Because it would look like you peed out pure water. You know how that is. You're all stoked to get all hydrated. And you're like, okay, I'm going to drink water every three minutes. You start drinking water and you think, God, I'm such a rock star, I'm going to be so hydrated. And the next thing you know, you're going pee every five minutes because, and then you're like peeing out the water that you just drank, that kills me. Why bother drinking it if you're just going to pee it out? That's because you are satisfactorily hydrated and you don't need to have your body in a hypo-osmotic environment. Like, dude, just pee out that extra water to maintain osmotic homeostasis. Your body knows, and there are hormones that can be produced and we're going to talk about them, but they can deal with this super dilute filtrate that exits distal convoluted tubule, that exits ascending loop of Henley. And actually, we all know this. You can reabsorb, you can continue to reabsorb water. In fact, you can make pee-pee that is a concentration of 1200 mls. So I'm going to let you just think about that. How would that be possible? That's the pee where you go in and you're like, whoa, I just peed out like orange madness because there's like hardly any water in that stuff because your body's like, I can't afford to put any water in your pee because we are too dehydrated. Did you follow that? My whole point is distal convoluted tubule, collecting duct, we're going to talk about their functions in more detail later on because both of them are affected by hormones. All right, shall we address this incredible medullary concentration gradient and figure out how exactly did we end up with that thing and why don't we just like suck it back out through the blood supply?