Nephron

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)...

Synonyms: Cortex renalis The kidneys are paired retroperitoneal organs of the Learning about kidney histology doesn’t have to be as painful as kidney stones! We have composed a simple step-by-step guide to help you master this complicated yet fascinating organ. If you need a little jump start, why not refresh your memory with our Key facts Gross anatomy Cortex (outer layer) and medulla (inner layer), calyces Nephron Main functional unit of the kidney: - Renal corpuscle; glomerulus and glomerular capsule - Renal tubule system; proximal tubule (convoluted and straight), nephron loop, distal tubule (convoluted and straight), collecting ducts Functions Urine production; maintains body fluid and electrolyte balance, blood pressure, acid base balance The kidney parenchyma consists of two layers; an outer cortex and inner medulla. They comprise around one million urine-producing nephrons. Urine is collected into a system of renal calyces, which is a series of distinctive chambers within a kidney. Calyces gradually increase in size, starting with the minor calyces, which open into larger major calyces, which empty into the renal pelvis, the urine passes into the ureter. The portion of the kidney which contains the calyces, renal pelvis, ureter and renal vessels is called the renal sinus. Kidney structure starter pack is waiting for you here: [Kidney histology] Now let’s take a closer look at the parenchyma layers. The renal cortex is the outer layer of the kidney tissue. It is...

\( \newcommand\) • • • • • • • • 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...

Recent Examples on the Web Each nephron servies as a filtering unit for blood running through blood vessels. — Bruce Y. Lee, Forbes, 17 May 2021 The filtered waste and extra fluid from the blood then goes into the nephron and then eventually down through the ureters as urine. — Bruce Y. Lee, Forbes, 17 May 2021 These examples are programmatically compiled from various online sources to illustrate current usage of the word 'nephron.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors.

Super late answer: The functional redundancy of the kidney holds multiple purposes. 1) Your kidney doesn't know "what the bad stuff is" Kidneys try and filter out 'everything' (used loosely here) and just take back what they know the body needs. This process allows this excretory organ to excrete potentially toxic compounds it hasn't seen before (beneficial to survival, so evolution likes that). 2) Functional redundancy allows the kidneys to finely tune ion concentrations More important than the kidney's excretory roles are its roles in homeostasis. The kidney is all about balancing ions in the body, and when this goes wrong it can lead to disastrous effects. Though the functional redundancy of excretion and resorption of ions is very energy intensive it allows the kidney to act as a fine-tuned hormone-sensitive scale of ion concentrations. As with all things in Biology, there is always some sort of (Bio)logical explanation due to the process of natural selection... Some of them are just less plainly visible! Hope that helps :-) respiration. all cells need to respire. everything in are bodies is made out of cells. cells->tissues->organs->organ systems->organism respiration needs glucose to combine with oxygen to form water carbon dioxide and energy. Energy is needed in our body obviously. Kidneys are also made from cells therefore they must respire. Kidneys are excretory organs. actually substances in the glomerular filtrate can be divided into high threshold,low threshold...