Countercurrent mechanism pdf file

Countercurrent exchange biology accessscience from mcgraw. The loop of henle is referred to as countercurrent multiplier and vasa recta as countercurrent exchange systems in concentrating and diluting urine. The mechanisms shown here are traditionally called the countercurrent multiplier and the countercurrent exchanger. Counter current mechanism by dr anita teli authorstream presentation. A model of countercurrent shunting of oxygen in the intestinal villus article pdf available in the american journal of physiology 2624 pt 2. Counter current mechanism everything you need to know. Medullary hyperosmolality and medullary gradient the interstitial fluid of the medulla is critically important in concentrating the urine,because the osmotic pressure of this fluid provides the driving force for reabsorbing water from both the descending thin segment and. Countercurrent definition of countercurrent by merriamwebster. Pdf countercurrent exchange in the renal medulla researchgate. The tubular fluid in the descending limb and the interstitial fluid quickly reach osmotic.

A system in which the inflow runs parallel to, counter to, and in close proximity to the outflow for some distance. Jpg to pdf convert file now view other image file formats technical details jpg is a graphical file format for editing still images, it offers a symmetrical compression technique which is processor intensive and time consiming in both compression and decompression. The principals of countercurrent multiplication, originally proposed by kuhn and ryffel in 1942. How to convert a jpg file to a pdf on a windows 10.

The effects of this enhanced countercurrent shear leads to a globally unstable flow field that is quite advantageous in combustion control. Counter current mechanism concentrated urine formation. A method of multiple liquidliquid extractions is countercurrent extraction, which permits the separation of substances with different distribution coefficients ratios. Read and learn for free about the following article. Initially studied in the 1950s by gottschalk and mylle following werner kuhns postulations, this mechanism gained popularity only after a series of complicated micropuncture experiments.

Scribd is the worlds largest social reading and publishing site. Links to pubmed are also available for selected references. Countercurrent multiplication was originally studied as a mechanism whereby urine is concentrated in the nephron. Lever federal republic of germany and glasgow, scotland boilermakers have known and exploited the principle of countercurrent exchange since the early nineteenth century.

Microsoft word q9 describe how the kidney maintains the medullary concentration gradient march 2011. Countercurrent mechanism in henles loop the nephrons involved in the formation of concentrated urine extend all the way from the cortex of the kidney to the medulla and are accompanied by. Countercurrent definition is a current flowing in a direction opposite that of another current. To conserve water, the countercurrent mechanism generates urine with osmolality greater than plasma. A countercurrent mechanism system is a mechanism that expends energy to create a concentration gradient. Cold water is pumped through one, and hot water through the other the inlets are at the opposite ends of the construction countercurrent. The nondimensional parameters that govern the mechanism have been determined in terms of the properties of the animal. Countercurrent exchange of solutes and water helping to preserve this gradient is indicated in the. Countercurrent multiplication refers to the process by which a small osmolality difference, at each level of the outer medulla, between fluid flows in ascending and descending limbs of the loops of henle, is multiplied by the countercurrent flow configuration to establish a large axial osmolality difference. Countercurrent shear flow control has been shown as an effective method of increasing volumetric heat release within a dump combustor due to an increase in turbulence, specifically the large turbulent structures present in the flow field. A model system for countercurrent transfer may be described in the following way.

Jul 01, 2008 the loop has a hairpin bend in the renal medulla. Find out information about countercurrent mechanism. Anatomy of the urinary system kidneys a pair of bean shaped organs located retroperitoneally, responsible for blood filtering and urine formation. For the record, i have no idea how this actually works. A clever design known as craig apparatus is used for this purpose lyman c. Pdf a model of countercurrent shunting of oxygen in the. Feb 15, 2009 video animation i did for some med students.

In both cases, the basic mechanism is the sameexchange of a substance between fluids flowing in opposite directionsbut the consequences are very different. Countercurrent mechanism helps penguin to stand on ice for long time. The function of the counter current mechanism is to create urine with a different concentration than that of urine. A mechanism is used when the required motion of bodies cannot be produced directly and the motion must be transformed. Countercurrent definition of countercurrent by merriam.

A current that flows in an opposite direction to the flow of another current. Counter current mechanism by dr anita teli authorstream. Traumatologia forense eduardo vargas alvarado pdf download. Countercurrently definition of countercurrently by the.

A simple free tool to count pdf pages in a folder and export the summary to notepad or excel. Substances are separated by this method on the basis of their different solubilities in two immiscible liquids. To do this, it uses a countercurrent multiplier mechanism in the medulla. Countercurrent exchange is a mechanism occurring in nature and mimicked in industry and engineering, in which there is a crossover of some property, usually heat or some chemical, between two flowing bodies flowing in opposite directions to each other.

The concentration of urine is controlled by antidiuretic hormone, which helps the kidneys to. Countercurrent mechanism overview the countercurrent mechanism partially contributes to generation of the corticopapillary osmotic gradient and is the product of juxtamedullary nephrons which possess long loops of henle that extend far into the renal medulla. The first takes place in the region of the nephron called henles loop. Countercurrent transfer in reproductive biology in. The purpose of this countercurrent exchange system is to produce hyperosmotic interstitial fluid in the medulla and hyposmotic filtrate leaving the loop of henle the water that leaves the descending loop of henle is absorbed into the vasa recta, which prevents dilution of the interstitial fluid. Best pdf resize software which can resize pdf to chosen file size. Countercurrent exchange is a mechanism organisms have evolved to maintain a certain optimality. In fish a countercurrent system in the gills increases the amount of oxygen dissolved in the water which is absorbed. It is found widely in nature and especially in mammalian organs. This could be maintaining an optimum core temperature, or optimum oxygen levels and water levels.

The mechanism s effect is dependent on the two fluids flowing in opposite directions, and having a concentration gradient between them. Countercurrent mechanism countercurrent multipliers the loop of henle produce high osmotic medullary gradient 1200 mosm lit at the. Countercurrent mechanism in henles loop the nephrons involved in the formation of concentrated urine extend all the way from the cortex of the kidney to the medulla and are accompanied by vasa recta. Countercurrent mechanism countercurrent multipliers the loop of henle produce high osmotic medullary gradient 1200 mosm lit at the bottom. Plate heat exchanger working principle, how a plate heat.

How does the counter current mechanism concentrate urine. Countercurrent mechanisms the mechanisms shown here are traditionally called the countercurrent multiplier and the countercurrent exchanger. When the blood first comes close to the water, the water is fully saturated with oxygen and the blood has very little. Countercurrent mechanism article about countercurrent. The countercurrent mechanism partially contributes to generation of the corticopapillary osmotic gradient and is the product of juxtamedullary nephrons which possess long loops of henle that extend far into the renal medulla. If you downloaded the pdf from the web or received it in an email, download the pdf again or ask the sender to resend it. In a countercurrent multiplier, the combined action of active pumping and circulation and recirculation of solutes around the loop of henle create an osmotic gradient with the following properties. This passive process is known as countercurrent exchange. Copy the file directly to your hard drive, rather than a thumb portable or network drive.

Loop of henle 1002 800 alh 400 402 200 dlh the countercurrent multiplier cortex medulla h 2o 1200 285 100 502 802 1100 1102 500 300 900 800 600 salt. You can add any number of pdfs and easily use this tool without any help. For example, it can refer to the process that is underlying the process of urine concentration, that is, the production of hyperosmotic urine by the mammalian kidney. Check out this collection of 30 pdf templates for cutandfold paper mechanisms and 3d optical illusions. Countercurrent distribution, in chemistry, a multistage solventextraction process, one of many separation methods that can be employed in chemical analysis. There is large vertical gradient from the top to the bottom of renal medulla. Give a brief account of the counter current mechanism. Countercurrent multiplier it is a mechanism involved in increasing the osmolarity of the interstitial fluid in the medulla of the kidney progressively to about 1200 to 1400 mosml. Industrial processes in chemical engineering or laboratory operations in which heat or mass or both are transferred from one fluid to another, with the fluids moving continuously in very nearly steady state or constant manner and in opposite directions through the unit. The movement of ions like sodium into the interstitial space causes water to passively diffuse out the descending loop of henle. Within the past few years, there has been a remarkable advance in our understanding of the mechanism by which the kidney is able to produce a concentrated urine. Although most programs can use either a jpg or pdf. The main function of this structure is to reabsorb water and ions from the urine. Countercurrent exchange of heat, respiratory gases, or nutrients is an important feature of the functional design of organisms, is.

To conserve water your body wants urine that is more concentrated than plasma when exreting extra water the osolarity of the urine will be less than that of plasma usually. Countercurrent flow definition of countercurrent flow by. Countercurrent definition of countercurrent by the free. Normal renal function hebrew university of jerusalem. Problem 11 kidney countercurrent system is represented by. The active ion pump of the thick ascending limb on the loop of henle reduces. There are two counter current mechanisms inside the kidneys.

This useful teaching aid was created for prof david poyner. Renal capsule a layer of fibrous connective tissue covering the kidneys. Run multiple iterations online to achieve desired pdf file size. The countercurrent flowarrangement of henles loop and the vasa recta traps salt and urea within the medulla and minimizes the volume of water entering the medullary interstitium. A countercurrent mechanism system is a mechanism that expends energy to create a concentration gradient it is found widely in nature and especially in mammalian organs. Open the new copy on your hard drive and print again.

Jpg to pdf convert your jpg to pdf for free online. Countercurrent exchange biology accessscience from. Assume that the loop of henle is filled with a concentration of 300mosml the same as. Get a printable copy pdf file of the complete article 1. Plate heat exchangers were first produced in the 1920s and have since been widely used in a great number of sectors a plate exchanger consists of a series of parallel plates that are placed one above the other so as to allow the formation of a series of channels for fluids to flow between them.

Biological countercurrent systems can be classified into two main types. Sequestration of urea and nonurea solutes in renal tissues of. Countercurrent mechanism definition of countercurrent. Counter current multiplication if youre seeing this message, it means were having trouble loading external resources on our website. For example, the rotor of an electric motor and the bearings in which it rotates do not form a mechanism, since in this case the electrical energy is transformed directly into the required motion without any intermediate transformation of mechanical motion. An analytical model for the countercurrent heat exchange mechanism in animals has been formulated and a solution has been obtained. Summary of the countercurrent mechanism the primary engineis active salt reabsorption without water by the thick ascending limb of henles loop. Renal cortex outer region of the kidneys where most enthrones is located. Adds more salt than water to the medullary interstitium, thereby osmotically concentrating the. An answer to query how to reduce pdf file size without losing quality compress pdf to chosen size.

Download these pdf files of incredible paper mechanisms. Explain counter current exchange giving one example from. Ttre function of the kidney is to regulate the composition of the blood plasrna. An animation to explain the kidneys role in balancing h2o and electrolytes by creating a concentration gradient in the nephrons. The stimulus for this recent burst of progress has been the introduction into the field of a revolutionary new concept. The countercurrent heat exchange mechanism, if dominant, was suggested as an energy conservation means since it provides a direct heat transfer path between the vessels.

A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Mechanism of hyperosmotic reabsorption in the tal there is apical nak2cl reabsorptive cotransport with k recycling through apical kchannels, and basolateral transport of na via the nakatpase and of cl via cl. To excrete water, the countercurrent mechanism generates urine with osmolality less than plasma. The renal handling of salts and water are independent of each other. Apr 23, 2009 countercurrent exchange is a mechanism organisms have evolved to maintain a certain optimality.

Introduction the countercurrent multiplier theory of the. Under certain circumstances operation in cocurrent mode surprisingly appeared to give better results than when run in countercurrent operation. Im sorry theres no sound, it wasnt my task to provide voice overs or narration. The flowing bodies can be liquids, gases, or even solid powders, or any combination of those.

Sometimes a pdf file becomes damaged or contains corrupt data. You can convert a jpg file into a pdf in windows 10 by changing some of the settings in your print menu. Jul 19, 2015 a detailed description on how counter current mechanism operates in our body. An analytical model of the countercurrent heat exchange. Concurrent flow to understand countercurrent flow, it is easiest to start by looking at concurrent flow where water and blood flow over and through the lamellae in the same direction. The plasma is the part of the blood that rernains when the cells been removed. The counter current mechanism operating inside the kidney is the main adaptation for the conservation of water. Linear stability theory was used to provide guidance into the global flow fields created within these facilities, all of which contain multiple unstable profiles, each having their own stability parameters.