 We're going to start looking at the gross anatomy of the kidney and we're going to do it in two different ways. We're going to look at a kidney that's just like hanging out and then we're going to look at a kidney that's been sliced in half. This is my sliced in half kidney and I'm actually going to draw the kidney for you because I think it's always valuable to draw pictures of your own structures. So, but I'm showing you this to let you know what I'm trying to draw and I'll probably go back and forth as we do this. So let's start by drawing our actual kidney and unfortunately, my brain cannot handle drawing the kidney in that orientation so I have to draw what? That was probably my left kidney. I'm going to draw my right kidney. Not that I can tell my left from my right and I'm going to try to make it huge but I have enough room to draw everything on it and now that I just made it this huge, I realized there's a structure that I want to draw on top that I'm not going to be able to draw on top but I'm going to just show you where it goes anyway. It's a little triangle shaped endocrine gland that sits on top of the kidney and it looks, it's a hat. This is the adrenal gland and you have two of them, one on each kidney and the adrenal gland has a whole bunch of endocrine function and you find them sitting right on top of the kidney. Okay, so our kidney is surrounded by a layer and I'm just going to draw this layer outside of here and I'm going to make it kind of get skinny over there and that's just because I don't want to get confused over what we're going to find around this little indentation that makes it look like a little kidney bean. You have a little bean in you. This is the fibrous capsule of your kidney and of course there's two names for it. It's also called the renal capsule. It's made of dense irregular connective tissue and it's just, it's like, it's just a covering that's found, there's also layers of fat that your kidney is kind of like embedded in in the posterior aspect of your abdominal cavity but I'm not, we're not going to focus on those guys. We're just going to focus on the actual kidney itself. Let's see here. There's this zone that we shall, maybe I just, well, well, how should we do this? This zone right here is called the hylum. Really? Oh, I'm pushing a button on my pen. No, we don't want to push that button. Although that's interesting to know that I can move the whole thing by pushing that button. The hylum of the kidney is the location of this indentation and I tell you that because there's several structures that come out of the hylum that are relevant. First of all, we have a structure that I'm drawing it in yellow because I want you to see that it's actually sort of continuous with this other microscopic structures that I'm going to draw in here. But this yellow structure heads to your bladder and it's called the ureter. It comes directly out of the kidney and when we cut the kidney open and take a closer look, you'll see like how the ureter is associated with the inside of the kidney. Also in the hylum, we have, okay, I'm going to draw this for you and then you have to guess what it is. It's my favorite. What, whatever could that be? It's the renal something, something you already know. It's the renal artery and look how huge it is. It's like gigantic. It's way bigger than the ureter, although you can't really tell that from my drawing. Who else would you expect? If we've got a renal artery going on, who else are you going to expect to see in here? Somebody that is most certainly blue got to have a renal vein. The renal artery, the renal vein and the ureter all exit the kidney in the same place, in this hylum. I'm just going to make these little ends so that you can see that that's just a blood vessel. Where do those go? Well, the renal artery brings blood from the descending abdominal aorta. The renal vein takes blood from the kidney back to the inferior vena cava. I think that's everything that I want to do external. Now imagine, we just chopped our kidney in half and now we're going to look inside and actually have a couple of layers, if you will, inside. And I'm going to draw my layers inside, super diagrammatic, but hopefully this will be clear. This whole area that is lined by the purple, this is the cortex. And we will see what kind of anatomical structures are found in the cortex of the kidney. The cortex is in contrast to the medulla of the kidney. So this whole area is the medulla of the kidney. Now the medulla has some significant anatomical structures and so I'm going to draw them for you. What? Can you imagine me doing such a thing? Okay, first of all, what you have to know is that my drawing is, of course, very diagrammatic. There are structures. What do these look like? Pizza slices. How do you know that? Oh my gosh, wouldn't it be fun if somebody out there actually thought they look like pizza slices? Who would think they look like pizza slices? If you thought pizza slices, you're very strange. Just like me. Okay, enough pizza slices. These are renal pyramids. That's easy, renal pyramid. Fantastic. Correct the falsi on an exam. Could be renal pyramids are found in the cortex of the kidney. Are they? No doggies. They're found in the medulla of the kidney. Now we'll look at the microscopic structure of what makes up a renal pyramid. But the tip of the renal pyramid has a name. It has a little nipoli name. Doesn't it kind of look like a little nipple? My face-to-face students this semester actually made fun of me because the papillary muscles, I must have said at some point, they're like little nipples. Because papilla means nipple, damn it. But they're like, dude, those don't look anything like nipples. It's just an expression. These are renal papilla, like little renal nipples. Renal papilla. And look at how many each renal pyramid terminates toward the middle of the kidney in a renal papilla. Now, this is going to hurt your head, so take a deep breath. The renal papilla is like a little nipple. And it actually is going to be able to drip pre-p. So your kidney is making urine. And before it actually is urine, it's like pre-urine. And the fluid that you are producing in your kidney is going to drip out of this little papilla. And here's the amazing thing. It drips out and there's a little funnel right next to it that's going to catch the little drops of pee-pee that are coming out of the papilla on each renal pyramid. So I'm going to draw you one of those. And I'm going to draw it in, I must draw it in this color blue. I just changed my mind. I must draw it in orange. That's going to help you. Now, look, it's a funnel. And so with my highly limited drawing skills, I'm drawing you a funnel. Do you see how if I had a funnel, oh my gosh, I feel like I really need a funnel, just like in the lectures where I really needed spaghetti noodles to demonstrate something for you, I really need a funnel right now. And the funnel sits right next to this and there's like a space in the funnel. The renal papilla drips pee-pee into the funnel. The funnel is called a minor calyx. I'm going to draw, I'm going to label it out here. This is the minor calyx. The minor calyx is really contiguous with the ureter. And so it's catching the pee-pee that's being produced in the renal pyramids. The renal pyramid has a minor calyx. And I closed that one off and I definitely don't want to close it off because they're not closed off. They really are like you could put a marble in the funnel and it could end up in your ureter. That'd be bad. That's like kidney stones. Don't do that. Don't put marbles in your ureters. Don't put them up your nose either. Okay. Minor calyces, that's plural of calyx. Minor calyces combine with other minor calyces. So this is like we're funneling into, look what just happened. Do you see what I just did? Two funnels, two minor calyces come together and make a, what do you think? It's this easy. We're going to make a major calyx, okay? So the minor calyx takes P from one renal papilla. The major calyx takes P from two minor calyces or more. And then guess what else happens? You can have multiple major calyces and they all feed into the same zone. Okay, I can't help it. I have to add this one in here too. Look. And I'm going to skip these guys just because I don't want to draw all of those. But look at, okay. I'm going to put a little green dot next to my major calyx. There's one, there's one. Here's one where we're bringing more than one together. I'm going to put a little red dot next to my minor calyx. Here's one, here's one, here's one. You guys are good? You totally get this idea. Okay, those are all minor calyces and they all feed into the renal pelvis. So part three, uh, renal pelvis. I meant to make that the same nice color as the other one. What color is that other one? I think it's yellow, but is it actually orange? My renal pelvis is the ultimate source. It's the last place where you're going to find urine in the kidney before it leaves and goes to the uriner. Okay? You know that's okay. There's someone I forgot in the renal medulla. But you're good, right? You know you're good. Look in my medulla, these things between my renal pyramids, what do they look like? Big old columns and their renal columns. I think renal columns. Sometimes I'm like, seriously, do we have to name that thing? Yes, I didn't just say that. Now, the P is going to get into the uriner. The uriner we know already is headed to the bladder. So let's look at that whole aspect of the urinary system.