Osmoregulation and the Nephron in Humans
11.9 هزار بار بازدید -
7 سال پیش
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This video further explains osmoregulation
This video further explains osmoregulation by showing the process that occurs in the human nephron.
Link to slideshow: https://docs.google.com/presentation/...
Link to document: https://docs.google.com/document/d/1s...
** If there are any pictures used in this video, they are NOT MINE and I will not take credit for them. **
TRANSCRIPT:
So, I’m kind of going over my previous video about osmoregulation, but today we’re focusing on the human kidney, which is the organ of osmoregulation and excretion. And here I’ve got a picture for you of what’s called the nephron, which is the smallest functional unit of the kidney. So you can kind of imagine that the kidney is made of all of these various structures, or nephrons, kind of like how your body is made up of various cells. It looks kind of confusing, but hopefully after watching this video, it’ll clear up some uncertainties about the whole process of osmoregulation.
Let me go ahead and label all of these for you first. This interesting conglomeration, I guess, of capillaries over here is called the glomerulus as a whole. And the thing surrounding it is what we call the Bowman’s capsule, since it’s kind of holding the glomerulus like a capsule would encase something. This U-shaped portion of the nephron is the “loop of Henle”, and you can actually see that this is one whole continuous tube. The first part of this before the loop of Henle is the proximal convoluted tubule, which, the name is quite appropriate seeing how convoluted it is, and the part after the loop is called the distal convoluted tubule. The distal convoluted tubule then leads on to a collecting duct, which is where the filtrate will begin its journey out of the body. Now these are just the basics of the nephron, and we’re going to dive in a little deeper to what each part of the nephron actually does.
So over here there’s a ton of blood pressure that’s basically forcing blood from the glomerulus into the Bowman’s capsule. This process is called filtration, and the filtrate coming from the glomerulus into the Bowman’s capsule contains a ton of valuable molecules, like vitamins, that we will need to extract. Now that the filtrate is in the Bowman’s capsule, it can move throughout the proximal convoluted tubule. So, what you’re going to see is that the proximal and distal convoluted tubules are kind of similar in function: the proximal convoluted tubule mostly absorbs molecules, such as glucose, amino acids, and sodium; meanwhile, the distal convoluted tubule is the one that reabsorbs sodium and chlorine. We also see a twin functioning mechanism down in the loop of Henle: the descending loop reabsorbs water, while the ascending loop pumps ions into the surrounding fluid which we call the interstitial fluid. But this doesn’t just happen all by itself. The salts in the loop of Henle are being actively pumped into the interstitial fluid to make the ion concentration here higher, meaning it’s becoming more and more hypertonic compared to the fluid in the loop. And remember, hypertonic just means that the concentration of solutes is higher. So now that the interstitial fluid is hypertonic to the fluid inside the loop, water will naturally diffuse into the interstitial fluid, and this happens in the descending loop of Henle. The reason why this occurs is because the descending loop is only permeable to water, meaning only water can pass through, while over here in the ascending loop, only ions can pass through. So what this totals up to is a very clever biological way of getting our bodies to reclaim water that would otherwise be excreted through urine.
Alright, so here’s a recap of what really goes on in your kidney: it’s made up of functional structures called nephrons, and each of these nephrons has multiple parts that do different things. A high amount of blood pressure forces the blood from the glomerulus into the Bowman’s capsule, in which filtration occurs and the filtrate is passed through the proximal convoluted tubule. Molecules are absorbed throughout this portion, and then water diffuses out from the descending loop of Henle. This is caused by the active transport of salts out of the ascending loop into the interstitial fluid, which causes the interstitial fluid to become hypertonic to the fluid inside the loop. Finally, in the distal convoluted tubule, more ions are absorbed through active selection, and from there, the remaining fluid begins its way out of the body.
Link to slideshow: https://docs.google.com/presentation/...
Link to document: https://docs.google.com/document/d/1s...
** If there are any pictures used in this video, they are NOT MINE and I will not take credit for them. **
TRANSCRIPT:
So, I’m kind of going over my previous video about osmoregulation, but today we’re focusing on the human kidney, which is the organ of osmoregulation and excretion. And here I’ve got a picture for you of what’s called the nephron, which is the smallest functional unit of the kidney. So you can kind of imagine that the kidney is made of all of these various structures, or nephrons, kind of like how your body is made up of various cells. It looks kind of confusing, but hopefully after watching this video, it’ll clear up some uncertainties about the whole process of osmoregulation.
Let me go ahead and label all of these for you first. This interesting conglomeration, I guess, of capillaries over here is called the glomerulus as a whole. And the thing surrounding it is what we call the Bowman’s capsule, since it’s kind of holding the glomerulus like a capsule would encase something. This U-shaped portion of the nephron is the “loop of Henle”, and you can actually see that this is one whole continuous tube. The first part of this before the loop of Henle is the proximal convoluted tubule, which, the name is quite appropriate seeing how convoluted it is, and the part after the loop is called the distal convoluted tubule. The distal convoluted tubule then leads on to a collecting duct, which is where the filtrate will begin its journey out of the body. Now these are just the basics of the nephron, and we’re going to dive in a little deeper to what each part of the nephron actually does.
So over here there’s a ton of blood pressure that’s basically forcing blood from the glomerulus into the Bowman’s capsule. This process is called filtration, and the filtrate coming from the glomerulus into the Bowman’s capsule contains a ton of valuable molecules, like vitamins, that we will need to extract. Now that the filtrate is in the Bowman’s capsule, it can move throughout the proximal convoluted tubule. So, what you’re going to see is that the proximal and distal convoluted tubules are kind of similar in function: the proximal convoluted tubule mostly absorbs molecules, such as glucose, amino acids, and sodium; meanwhile, the distal convoluted tubule is the one that reabsorbs sodium and chlorine. We also see a twin functioning mechanism down in the loop of Henle: the descending loop reabsorbs water, while the ascending loop pumps ions into the surrounding fluid which we call the interstitial fluid. But this doesn’t just happen all by itself. The salts in the loop of Henle are being actively pumped into the interstitial fluid to make the ion concentration here higher, meaning it’s becoming more and more hypertonic compared to the fluid in the loop. And remember, hypertonic just means that the concentration of solutes is higher. So now that the interstitial fluid is hypertonic to the fluid inside the loop, water will naturally diffuse into the interstitial fluid, and this happens in the descending loop of Henle. The reason why this occurs is because the descending loop is only permeable to water, meaning only water can pass through, while over here in the ascending loop, only ions can pass through. So what this totals up to is a very clever biological way of getting our bodies to reclaim water that would otherwise be excreted through urine.
Alright, so here’s a recap of what really goes on in your kidney: it’s made up of functional structures called nephrons, and each of these nephrons has multiple parts that do different things. A high amount of blood pressure forces the blood from the glomerulus into the Bowman’s capsule, in which filtration occurs and the filtrate is passed through the proximal convoluted tubule. Molecules are absorbed throughout this portion, and then water diffuses out from the descending loop of Henle. This is caused by the active transport of salts out of the ascending loop into the interstitial fluid, which causes the interstitial fluid to become hypertonic to the fluid inside the loop. Finally, in the distal convoluted tubule, more ions are absorbed through active selection, and from there, the remaining fluid begins its way out of the body.
7 سال پیش
در تاریخ 1396/02/22 منتشر شده
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