But this is an important structure, to at least get a sense for how it looks and what the different parts are called. By allowing for reabsorption of water and some electrolytes back into the blood, the nephron also plays a vital role in the maintenance of normal fluid balance in the body. There are two main hormones that regulate the rate of excretion of water. This allows for the reabsorption of more or less water, according to the needs of the body. So let's say I take that little guy and show you on the left side of the screen what that would look like. The fluid that has passed through the distal convoluted tubules is drained into the collecting duct far left-hand-side of the diagram above.
When enough red blood cells have been produced, this process is shut down via a negative feedback mechanism. The descending loop of Henle consists of an initial short, thick portion and long, thin portion, whereas the ascending loop consists of an initial short, thin portion followed by a long, thick portion. The kidneys are two bean-shaped organs located outside the peritoneum at the posterior of the upper abdomen. Renal Hilum The renal hilum is the entry and exit site for structures servicing the kidneys: vessels, nerves, lymphatics, and ureters. And when it does we call it the Efferent arteriole. As the glomerular filtrate progresses through the tubule, these capillary networks recover most of the solutes and water, and return them to the circulation. Reabsorption Sodium chloride, calcium and water are reabsorbed from the collecting duct back into the blood stream.
Podocytes bears finger like projections known as podocels. Tubular Reabsorption During this phase, all parts of the tubule act to return essential substances out of the nephron so that it is not lost in the urine. The second layer is called the perirenal fat capsule, which helps anchor the kidneys in place. And so this is an important structure, and we'll talk about different parts of the nephron in future videos. The limbs of the loop of Henle are permeable to certain ions, and solutes and water is reabsorbed from the collecting ducts that pass through this area. And in fact, this little network of blood vessels, if you look under a microscope, is actually being hugged by something like this. The function in the kidney is mainly concerned with filtration, reabsorption, and secretion of various solutes, carbohydrates, and glutamate.
Ureters, blood vessels, lymph vessels, and nerves enter and leave at the renal hilum. Some of the substances pass through the space between the epithelial cells while others through the cells itself. Which is the correct order of blood flow? In the process, macronutrients, electrolytes and the required amount of water are retained while waste substances, excess electrolytes, micronutrients and toxins are expelled. This is the first time we're taking a look at something that is not a blood vessel in the kidney, and it begins our journey of urine. External Website Visit this to view an interactive tutorial of the flow of blood through the kidney.
The adrenal cortex directly influences renal function through the production of the hormone aldosterone to stimulate sodium reabsorption. This is the only portal system in which an arteriole is found between the first and second capillary beds. The artery-- or the arteriole, rather, starts making a lot of little turn-backs on itself and finally straightens out. Because the kidney filters blood, its network of blood vessels is an important component of its structure and function. A renal artery-segmental artery-interlobular artery-peritubular capillaries- afferent arterioles B interlobar arteries-arcuate arteries-glomerular capillaries-arcuate veins C arcuate veins-arcuate arteries- glomerular capillaries- renal vein D renal vein-segmental arteries-interlobar arteries- efferent arterioles E interlobar veins- afferent arterioles- efferent arterioles- glomerular capillaries Which is the correct order of filtrate flow? As a nursing student, you must be familiar with the basic structure of the kidney and its. The diameter of the efferent arteriole is smaller than that of the afferent arteriole, which helps maintain a fairly high blood pressure in the glomerulus. And it's called Afferent because it's headed toward something.
The surface area for reabsorption is facilitated by the lining of simple cuboidal epithelium in them. This will lead to reduced blood pressure. About 15 percent of nephrons have very long loops of Henle that extend deep into the medulla and are called juxtamedullary nephrons. The others have a vein. The glomerulus is a network of intertwined capillaries mass.
The water and solutes remaining in the tubules become urine. But you're probably still wondering-- oh actually, I didn't label this for you. Collecting Duct Collecting duct is a long, straight tube where H+ and K+ ions are secreted to maintain the electrolyte balance of the blood. Excretion Components of urine are water, sodium chloride, calcium, potassium, bicarbonate, creatinine and urea. Mesh-like structure of the collagen fibers filters the blood by a process known as ultrafiltration.
The renal cortex is granular due to the presence of nephrons—the functional unit of the kidney. Such contraction and relaxation regulate blood flow to the glomerulus. But if more hydrogen ions are retained in the blood, this renders the blood more acidic less alkaline. The pedicels interdigitate to form filtration slits, leaving small gaps that form a sieve. It's coming from the renal artery headed towards something, and that something is this. The renal arteries arise directly from the aorta, and the renal veins drain directly into the inferior vena cava.
Let's see if you can guess before I finish this drawing. Fenestrations allow many substances to leave the blood based primarily on size. Microanatomy of the Nephron Renal Corpuscle As discussed earlier, the renal corpuscle consists the glomerulus and the glomerular capsule. The ascending limb is more permeable to salts as compared to water, and the active absorption of salts causes more water to be pushed out through the descending limb, resulting in the formation of concentrated urine. It comes from the efferent arterioles. By accessing any content on this site or its related media channels, you agree never to hold us liable for damages, harm, loss, or misinformation.