Nephron structure

\( \newcommand\) • • • • • • • • The nephron of the kidney is involved in the regulation of water and soluble substances in blood. Key Points • The glomerulus is the site in the nephron where fluid and solutes are filtered out of the blood to form a glomerular filtrate. • The proximal and distal tubules, the loop of Henle, and the collecting ducts are sites for the reabsorption of water and ions. • All of the glucose in the blood is reabsorbed by the proximal convoluted tubule through ion cotransport. • The loop of Henle (sometimes known as the nephron loop) is a U-shaped tube that consists of a descending limb and ascending limb, which differ in permeability. • The collecting duct and distal convoluted tubule are normally impermeable to water, but this is altered due to hormone stimulus during homeostasis. Key Terms • Bowman’s capsule: A cup-like sac at the beginning of the tubular component of a nephron in the mammalian kidney. • proximal tubule: The first and primary sort of water and ion reabsorption in the kidney, where all glucose in the blood is reabsorbed. • glomerulus: A small, intertwined group of capillaries within the nephrons of the kidney that filter the blood to make urine. A Nephron A nephron is the basic structural and functional unit of the kidneys that regulates water and soluble substances in the blood by filtering the blood, reabsorbing what is needed, and excreting the rest as urine. Its function is vital for homeostasis of blood volume, blood pressur...

Ranaa Aboumosallam Arafat I took pre-masters and diploma in Microbiology, Human Physiology and Endocrinology. I got accepted to start my masters next fall at the University of Manitoba in Biology. I wrote lessons for Michigan virutal and I worked as a biology teacher for one year. Moreover, I wrote scientific explainers and presentations for several educational platforms. • Instructor There are three parts to nephrons: 1- Renal corpuscular consists of the glomerulus and bowman's capsule and has a role in blood filtration. 2- Renal tubules consist of distal and proximal convoluted tube and loop of Henle and have a role in reabsorption of essential nutrients back to the blood. 3- Collecting duct collects urine and passes it to the ureters to be expelled later through the urethra. Kidneys The kidneys are two small organs that do one big job: filter the blood to create urine. Hopefully, you already take a moment to appreciate your kidneys each time you're in the bathroom, but if not, this lesson will help nudge you into giving the kidneys the credit they deserve. Within the kidneys, you have tiny, microscopic structures called nephrons. If the kidneys are urine-making factories, the nephrons are the workers within those factories who actually make the urine. You have approximately one million nephrons per kidney doing the job of filtering the blood and producing urine. We're going to take a close look at the nephron and what occurs within them to make that wonderful urine we e...

Learning Objectives By the end of this section, you will be able to: • Distinguish the histological differences between the renal cortex and medulla • Describe the structure of the filtration membrane • Identify the major structures and subdivisions of the renal corpuscles, renal tubules, and renal capillaries • Discuss the function of the peritubular capillaries and vasa recta • Describe the structure and function of the juxtaglomerular apparatus • Describe the histology and functional significance of the proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting ducts Nephrons are the “functional units” of the kidney; they cleanse the blood of toxins and balance the constituents of the circulation to homeostatic set points through the processes of filtration, reabsorption, and secretion. The nephrons also function to control blood pressure (via production of renin), red blood cell production (via the hormone erythropoetin), and calcium absorption (via conversion of calcidiol into calcitriol, the active form of vitamin D). Each nephron consists of a blood supply and a specialized network of ducts called a tubule. For each nephron, an afferent arteriole feeds a high-pressure capillary bed called the glomerulus. Blood is filtered by the glomerulus to produce a fluid which is caught by the nephron tubule, called filtrate. The proximal end of the tubule that surrounds the glomerulus and catches the filtered fluid is the glomerular (Bowman’s) capsule. ...

Nephrons: The Functional Units of the Kidney. Nephrons take a simple filtrate of the blood and modify it into urine. Nephrons are the “functional units” of the kidney; they cleanse the blood and balance the constituents of the circulation. Each kidney is made up of over one million nephrons that dot the renal cortex, giving it a granular appearance when sectioned sagittally. Many changes take place in the different parts of the nephron before urine is created for disposal. The term forming urine will be used hereafter to describe the filtrate as it is modified into true urine. The principle task of the nephron population is to balance the plasma to homeostatic set points and excrete potential toxins in the urine. They do this by accomplishing three principle functions—filtration, reabsorption, and secretion. They also have additional secondary functions that exert control in three areas: blood pressure (via production of renin), red blood cell production (via the hormone EPO), and calcium absorption (via conversion of calcidiol into calcitriol, the active form of vitamin D). Tubular parts of a Nephron – converts the filtrate into urine • The Bowman’s capsule / Glomerular capsule: The Bowman’s capsule (also called the glomerular capsule), is the beginning of a nephron. It surrounds the glomerulus. It is a double walled cup, It is composed of inner visceral and outer parietal layers. Parietal (outer) layer of glomerular capsule is simple squamous epithelium. Visceral (inner)...