the urinary system which is our last full organ system for the semester how crazy is that I say that because we're going to do reproduction but we're we run out of time and so we put it on the final exam so you're gonna have 30 questions of reproduction on the final and 50 questions from the rest the semester for an 80 point test so you already have the review guide for that it's in the back of your class packet but the urinary system is a very difficult chapter and it's a very important chapter especially if you're heading into nursing that we understand this the reason why I think it's difficult is it just ties in a lot of other organ systems however I get lots of people lekha days on this because I think because you have to study it you have to understand it people usually spend the time so this is also called the excretory system and in fact for the longest time that's what textbooks called it however urinary is better because other systems excrete waste right and so your lungs are getting rid of what waste we just did the respiratory system not that long ago to get rid of all that carbon dioxide the digestive system we had the defecation reflex boy was that exciting and in the skin or nitrogenous wastes that are released or the skin releases those nitrogenous wastes in your sweat if you remember sweat has one 130th the concentration urine in it you and so even though that's less than 1% I am NOT happy about that so the point is your body has to get rid of waste and so although we rely on some systems to do the majority of that other systems do it too so urinary system is better because this is actually just making the urine we always start every chapter with what's the point so the functions of the urinary system there's a lot going on here it should just be everybody pees and we're done but it's way more complicated than that so what I have done here on this bottom paragraph is I cut and pasted from later in the notes and that's because when studying I don't like to have to flip ahead so when I'm like reviewing for the test and I can't remember what all the stare on is I went ahead and kind of answered that so right now we're just focusing on the big we're just focusing on that like dark greenish color later on we'll focus on the bottom part but that's just there because like I said when you're studying later it'll be there so right now we're just staying real general so general functions removing metabolic wastes that's the biggest thing we've got to clean the blood so our body is like a machine it's gonna make tons of waste while it's doing its job while it's doing its work so we have to make sure we get rid of that what another huge role the urinary system is regulating osmotic pressure in our body fluids we have to make sure that the water is the right percentage in both our blood urine everything by assuring for the most part that what we intake is what we output so this is water balance right we don't want to gain or lose twenty pounds of water weight in one day so how do we do this well we're going to use hormones that we had back when we did hormones the antidiuretic hormone which was from your pituitary gland so remember that's the one that causes you if you drink alcohol it shuts off a th and then you pee all the time so that's the big one normally you're anti water loss but we also had Aldous Tehran from the adrenal glands and that guy member was the one that forced us to suck in sodium so we just saw that with digestion it's like Al the straw or al the starin helps us absorb sodium and our large intestine so that way water follows like a puppy because we don't want squirty duties so it's a bass-ackwards way of keeping water in your body is the fact that al the star on help so you absorb Saudi so both of these hormones are affecting water balance just to make sure that for the most part we're not peeing ourselves to death right the nation obviously the most water that you lose all days from peeing I mean you do this right so you know this regulating volume composition and pH of body fluids expected especially the blood so remember the blood is real picky the composition of your blood is really exact it has to be you know 55% plasma and of that 55% of plasma we're going for you know 7% proteins and the rest being water I mean it's like those percentages for the blood were crazy for the pH of your blood your blood had to be between seven point three five and seven point four or five so your urinary system is going to help maintain that since it's cleaning the blood it's a way that you're going to release hydrogen ions hydrogen ions are what acidify our blood so we're gonna be getting into all this it's just like I said an overview of the functions of the urinary system at this point a wreath row poitain we saw that guy before remember that's the hormone that's the hormone that your kidneys release and tell your bone marrow to root to make a wreath row site to step up your blood production so that's gonna affect the volume of your blood the density of your blood as well as blood pressure so renin and angiotensin we're eventually gonna see their roles on this we haven't seen these guys yet that's what this chapter is all about when I went ahead and cut and pasted so that way you wouldn't have to flippety-flip when you're stuck studying for this test all of the complexities of how urine is made because man is it complicated and we're going to be making some drawings kind of like we did for capillary exchange so you're gonna want a piece of paper and something to write with when you get to that lecture and we're gonna add to our drawing as we kind of go through this but for now it's just the basic anatomy we've already had this lab so we have the kidneys and remember the kidneys aren't straight across from each other the left side is just a little bit higher than the right we have the ureters which are the tubes that bring the urine to the bladder and so those guys are really really long as they may enter their way through there to the bladder and the Neri throw it shares the urine to the world you so the kidneys are actually a lot higher up than where most people assume like most people will touch their lower back and be like oh I think my kidneys are infected I'm like oh they're about you know eight inches higher than that so they're actually outside the parietal peritoneum so they're actually outside that protective sac that's in your abdomen and so we call this retroperitoneal like if you wear retro clothes or you're into retro music you're kind of like outside the normal right because that's kind of something different kind of alternative so retroperitoneal really just means outside the peritoneum because of that your kidneys are very very vulnerable like in a car accident or if you get like an upper cut punch to your kidneys I mean that's a cheap shot and people just kind of fall down because it like decreases their blood pressure so rapidly so the kidneys are very very vulnerable and easily damaged because they're not as protected to some of your other organs because of that they have tons of fat around them so the left side a little bit higher than the right they have a renal fossa which is it's a bunch of connective tissue and fat to keep them in place and protect them a little bit there's a fibrous capsule which I think looks like the skin on a kidney bean which kind of gives the kidney its overall shape you we have the hilum which is the space that the blood vessels go in and out of the kidney as well as the renal pelvis so we have the same word for the lungs the hilum on the lungs is where the pulmonary arteries and veins go in and out of the lungs as well as the primary bronchi the renal sinus sinus means face and so it's a the root of the kidney where you got again blood vessels and you have a lot of fat most organs have a cortex and a medulla so the cortex is always the outer part the medulla is the OE gooey center so on this picture here it's showing you the renal cortex as being kind of that lighter edge all the way around the kidney and it has these it kind of dips in and we call those now the renal columns so the renal columns if you look at this picture it's labeled 3 up from the bottom there it's just showing you how that cortex dips between those structures that look like paintbrushes so we just call them then the renal columns so the renal columns are just part of the cortex where it dips down we have the renal medulla the dark gooey gooey Center and that guy is made up of renal pyramids so the renal pyramids look like little triangles they I said in lab how I think they kind of look like little paint brushes okay so the medulla is the region the pyramids of specific structures just like you know I'd say the Midwest is a region Indiana's a specific state within it so the module is the dark we center and so if I tagged that on a lab practical that's what I usually say I say like what is the center of the kidney called so the renal pyramid if you look at them they're striated they're striped right well the reason that happens is you have microscopic little collecting ducts little tubes that are basically going to make the urine and so when you pile a bunch of microscopic stuff you can see it with the naked eye but that's why it kind of looks like that structure the renal papilla so if we think each pyramid comes to a tip again if it kind of think of it like a paintbrush it's where the handle attaches so where it tapers to a point where it tapers to a tip we call that the renal papilla or papilla because that means finger like projection so the whole point of the pyramid like a funnel so if you use a funnel you're funneling everything down to a point right to fill up a bottle or something so we're filtering or we're funneling all of the urine to get it out of the kidney so the first place this urine is going to dump is what we call the minor calyx which is that little cup like structure that looks like the handle on the paper crash into the minor calyx the first cup like structure when two of those merge together or more could be three like this picture is the major calyx then when though those merged together then you're in the renal pelvis and so if you think of the kidney like a piece of fruit the renal pelvis is the stem and then further on down the line it's your ureter which we saw on the first slide and that's what's actually sending the kid the urine to the bladder the kidneys are all about cleaning the blood so they have a massive blood supply so we have to renal artery in the renal vein which we've seen before so the renal artery is going to ultimately connect to the aorta the renal vein is going to connect to that inferior vena cava but this picture here you can see how that blood just like splits out because it's got to be cleaned that's the whole point of the kidney so we're not doing like inter lobular arteries and veins or segmental arteries but just keep in mind that the the kidney is bloody as hell you so if you take a kidney like this picture here letter A and you blow up just one of the renal pyramids so in this picture here you can see the renal cortex the outer the medulla the inter but this is just showing one pyramid the renal capsule is shown in that picture is being kind of the skin on the get me so this is highlighting one nephron you've got over a million of these per kidney piled on top of each other which is why the renal pyramids look strided why they look striped so this is just blowing up one nephron so we can see this so this will be where we'll spend so much time because the nephron is what we call the functional unit of the kidney because the nephron is what does the function of the kidney the kidneys jobs to make nerve make urine that's what the nephron does so if you remember like from muscle contraction in A&P one the sarcomere was the functional unit of a muscle because a sarcomere is what contract acts and allows a muscle to contract so it's the smallest microscopic thing inside your muscles that slide together so it's the same thing here this is a microscopic thing but this is where urine is made so we're bringing the blood in and out we have the afferent arteriole bringing things in efferent remember exit bringing thing things out we have that little capillary bed curled in there that's that Ghulam eulerís we have the outer cup like structure that has 75 names globular capsule or I call it Bowman's capsule so remember from lab this is a crucial meeting point between two organ systems this is the crucial meeting point between car are do and urinary and so the cardio's job is to deliver oxygen pick up waste live his life right and he's trying to get that blood around your body every minute all day long the urinary stop is to clean the blood so the urinary would rather spend hours cleaning that blood but it can't because the blow but has his agenda the Bloods got places to go so this is like pulling in and out of car wash as quickly as possible because you have other things to do right the blood is gonna get in and out of Bowman's capsule really really quickly so while that capillary is curled around in there is the only time we're going to get to siphon off this gang to get the dirty stuff out of that blood so when we do that we call it filtrate because we don't make urine yet okay until it's like committed to leave your body we don't really call it urine we call it filtrate the reason we do that is there's a lot of good stuff in that filtrate that we have no intention of getting rid of so that's why the nephron looks like this this design which is crazy okay where you have the proximal convoluted tubule how twisty and convoluted that is the descending limb and a sending limb of the nephron loop the distal convoluted tubule and the collecting duct it always goes that order PCT descending a sending DCT collecting duct it's all poison that or but if you're looking at this and you're like what the hell why can't it just be straight why does it have to be so damn complicated well it's because this is based on the ultimate idea of changing your mind there's plenty of time as the filtrate is moving through the nephron for us to say you know what I really don't want to get rid of that stuff so this is based on the idea that that cardio is flying in and out of there so freaking fast that if I'm the urinary system I may grab too much stuff out of that Bloods because if I'm panicking and I'm just trying to grab as much waste as possible I may grab some good stuff too but that's okay because if good stuff ends up in the proximal convoluted tubule or in the descending limb or in the ascending limb or the distal convoluted tubule I can have time to pull it back into the blood because until it hits that last step until it hits that collecting duct I can change my mind so that's why this thing is so screwie it has a really important purpose it's based on the idea that you can change your mind and take these back seats which is what I just showed you the functional unit of the kidney which we separate into two things the renal corpuscle is where we filter which will make more sense as we get into this right now we're just thinking of the anatomy we have the ghulami lewis which is the blood and then we have Bowman's capsule which is the urinary and then we have the renal tubule which is the proximal convoluted Julio's the loop of Henle which is the descending in a sending limb and distal convoluted tubules