THE KIDNEY AND THE CONCEPT OF CLEARANCE*
|
|
- Jason Tucker
- 6 years ago
- Views:
Transcription
1 THE KIDNEY AND THE CONCEPT OF CLEARANCE* I. The Antomy of the Mmmlin Kidney A. Gross ntomy: 1. The outer region of the kidney = the CORTEX 2. Inner region = the MEDULLA 3. The re where ll of the urine collects is clled the PELVIS OF THE KIDNEY. The urine leves the kidney's pelvis vi the URETERS b. The pelvis is lso where the blood supply enters nd leves the kidney vi the RENAL ARTERY AND RENAL VEIN. Incidentlly, bout 25% of the crdic output flows through these vessels. cortex medull "renl pelvis" ureter B. Histology 1. The functionl units of the kidney re clled NEPHRONS. Of these, there re two types:. CORTICAL (SUPERFICIAL) NEPHRONS: The entire nephron is locted in the outer region, the cortex. These function primrily in secretion nd rebsorption of different substnces. b. JUXTAMEDULLARY NEPHRONS: these nephrons strt in the Cortex nd extend down into the medull, in some cses to ner the pelvis of the kidney. Besides being involved in secretion nd rebsorption of mterils, their unique role is in concentrting the urine. c. Morphologiclly, the difference between corticl nd juxtmedullry nephrons besides their size nd loction is the size of their LOOPS OF HENLE (see below) - - Corticl nephrons essentilly lck long loop of Henle. d. The Rtio of Corticl to Juxtmedullry nephrons is n index of the bility of n niml to concentrte its urine. The more juxtmedullry nephrons, the more the urine cn be concentrted. We will tke this up in more detil in the next clss. 2. Histology of Juxtmedullry Nephron. GLOMERULUS: The filter of the nephron. Essentilly, it consists of two prts: 1. A cpillry tuft tht is highly convoluted; it is surrounded by: * Copyright 2015, Kenneth N. Prestwich, Holy Cross College, Worcester, MA kprestwi@holycross.edu Excretion by the vertebrte kidney: Clernce 1
2 2. A cup- like lyer of epithelil cells clled Bowmn's Cpsule. Notice in the digrm below tht the cpsule cn be seen s hollow bll tht hs been pushed in with fist where the fist is mostly surrounded by the bll. The fist represents the cpillry tuft: fferent rteriole cpillry tuft (glomerulus) filtrtion filtrte proxml convoluted tubule efferent rteriole Bowmn's Cpsule 3. The ction of the cpsule will be reviewed lter in detil, but suffice it to sy tht wter nd solutes re filtered through the cpillry wlls nd the wlls of the cpsule nd end up in the CAVITY OF THE BOWMAN'S CAPSULE s Glomerulr FILTRATE or simply FILTRATE. b. PROXIMAL TUBULE: This is n re where mterils re pssively nd/or ctively secreted nd re- bsorbed. Most of the wter nd solutes (67%) tht were filtered re pssively n ctively rebsorbed here. c. LOOP OF HENLE: This is very long in the juxtmedullry nephron. It hs very complex function tht will be reviewed lter. It consists of: 1. Two thin tubules tht re linked together. The cells lining these tubules re very thin nd lck lrge numbers of mitochondri; they re not involved in ctive trnsport.. The DESCENDING THIN LIMB which crries filtrte towrds the pelvis of the kidney where it mkes HAIRPIN TURN nd becomes the scending thin limb (see below). No significnt solute rebsorption occurs here; however this section of the loop of Henle is permeble to wter. For resons tht will be explined lter, bout 17% of the filtered wter is rebsorbed here. b. the ASCENDING THIN LIMB which crries filtrte bck towrds the cortex nd the thick scending limb (see below). No significnt trnsport occurs here. It is wter impermeble. 3. THICK ASCENDING LIMB: n re where much ctive trnsport of solutes occurs. For instnce, bout 25% of the filtered N + is rebsorbed here. This section is lso wter impermeble nd s result of the fct tht wter cnnot move while solutes re pumped out, the osmolrity of the fluid leving this section is extremely low (bout 150 mosm). Excretion by the vertebrte kidney: Clernce 2
3 d. DISTAL CONVOLUTED TUBULE (DCT): this section is the lst region of the nephron nd is primrily concerned with the regultion of N +, K + nd H + vi secretion nd rebsorption. Its ctions re under the control of the steroid hormone ALDOSTERONE. More bout ldosterone in the next clss. Together with the collecting duct, bout 12% of the filtered N +, Cl - nd 15% of the filtered wter re rebsorbed in the DCT. e. Not relly prt of the Nephron, but connected to it is the COLLECTING DUCT, tube tht tkes filtrte from the distl convoluted tubule nd moves it to the pelvis of the kidney. In the process, depending on the levels of the hormone VASOPRESSIN (lso clled VASOTOCIN nd ANTI- DIURETIC HORMONE or ADH), wter my be removed from the filtrte nd the urine mde more concentrted. The endocrine system hs n extensive role in regulting the secretion nd rebsorption processes of the kidney. Below is tble tht summrizes the hormones nd their trgets nd effects. We will look t some of these in detil lter: Segment Hormone Effects Prox. Conv. Tubule Thick Ascending Loop Distl Tubule nd Collecting duct Prthyroid Hormone Angiotensin Aldosterone, Clcitonin, Glucgon, Vsopressin, Prthyroid Hormone Clcitonin Vsopressin Aldosterone Prostglndins Brdykinin NCl nd wter rebsorption NCl nd wter NCl rebsorption NCl rebsorption Permebility to wter nd NCl rebsorption NCl rebsorption NCl rebsorption NCl rebsorption 3. CIRCULATION:. Blood enters the kidney vi the RENAL ARTERY b. This eventully splits into lrge number of smll ARTERIOLES, mny of which serve s the blood supplies of the glomeruli. Thus, their blood will be filtered. c. The ctul rteriole tht enters the glomerulus is clled the AFFERENT ARTERIOLE. d. The blood then moves through the glomerulr cpillries nd is filtered. e. The blood leves the region of the Bowmn's cpsule vi the EFFERENT ARTERIOLES f. Most of this blood now enters the PERITUBULAR CIRCULATION, group of vessels tht surround the convoluted tubules nd the loop of Henle nd collect the mterils Excretion by the vertebrte kidney: Clernce 3
4 tht come out nd lso ct s the source for mterils tht will be secreted. They lso supply oxygen nd other substnces nd removes wstes from these tissues. g. In juxtmedullry nephrons, bout 0.7% of the blood circultes through series of scending nd descending vessels clled the VASA RECTA. These re ssocited with the loops of Henle, these vessels re rrnged s counter- current exchnger (see digrm on the next pge). They perform n importnt tsk in helping to concentrte the urine. (This will be mentioned in more detil in the next lecture). II. FORMATION OF THE GLOMERULAR FILTRATE: A. Formtion of the filtrte is simple physicl process identicl to the formtion of interstitil fluid nd lymph tht we discussed erlier with the circultion. The min difference is tht the pores in the filtering cpillry (glomerulus) re bit lrger thn in regulr cpillries nd the "other side of the filter", the lumen of the Bowmn's cpsule, cn be through of s hving reltively low hydrosttic pressure s compred to the interstitil fluid. In ny cse, s with the other cpillries, filtrtion is governed by: hydrosttic nd colloidl osmotic pressures nd by the size of the filtered molecules reltive to the pore size in the filter nd by the chrge of the filtered prticles. Here we will focus primrily on the filtrtion of wter; relize tht other mterils tht re smll enough to pss the membrne will come long for the ride. Most of this will be review, with the exceptions being more explicit discussion of chrged prticle size nd more on regultion of blood flow. B. The influence of prticle size nd chrge on filterbility cn be illustrted with n experiment where dextrns (hrmless, non- metbolizble crbohydrtes of different moleculr weights) with vrious mounts of ionic groups ttched re dded to blood nd their concentrtion in the Bowmn's spce is mesured. Here is tble tht summrizes the bility of mterils to pss through the glomerulr filter. The figure below shows the rtio of the concentrtions of given mteril tht is in the filtrte (C f ) to tht in the plsm of the tubule (C p ). Thus rtio of C f / C p tht is ner unity implies tht the substnce is freely permeble, if it is less thn one the mteril is only prtilly permeble or is impermeble (C f /C p = 0). wter NCl 1.0 myoglobin C f / C p 0.5 glucose inulin fter Fig. 45-5, Berne nd Levy, Physiology, Mosby 1983 hemoglobin lbumin Moleculr Rdius (10-10 m) Excretion by the vertebrte kidney: Clernce 4
5 C. Assuming tht mteril is filterble, the rte tht mteril psses through the filter, s we lerned previously, is described by the STARLING HYPOTHESIS: 1. Filtrtion Rte = k * (P GC + Π BS ) - (P BS + Π GC ) where k is fudge fctor coefficient tht describes how fst fluid moves cross the glomerulus t given filtrtion pressure, P GC is the hydrosttic pressure of the glomerulr cpillry, P BS is the hydrosttic pressure in the Bowmn's spce (Bowmn's cpsule), Π GC is the glomerulr cpillry colloidl osmotic pressure nd Π BS is the sme mesure for Bowmn's spce. 1. Let's look t this eqution in detil. IF EVERYTHING ELSE REMAINS CONSTANT: 2. if the cpillry hydrosttic pressure (P GC ) increses or the tubulr hydrosttic pressure decreses, there will be greter pressure tending to drive mterils cross the membrne nd the filtrtion rte will increse. 3. By contrst, reltively higher Bowmn's spce osmotic pressure (Π BS ) will tend to encourge fluid to leve the cpillry s will reltive lower tubule osmotic pressure. 4. We cn envision the net forces of ech of the hydrosttic nd osmotic pressures s: Hydrosttic Filtrtion Vectors To Tubule Osmotic Grdient Net Rte of Filtrtion To Cpillry Distnce Along Glomerulus (sme s bove) NOTE: By n exctly nlogous mechnism, the blood forms lymph in the tissues of the body. IN SUMMARY, REALIZE THAT THE GLOMERULUS- BOWMAN'S CAPSULE ACTS AS A SIMPLE PHYSICAL FILTER AND THAT FOR FREELY FILTERABLE MATERIALS, THE CONCENTRATION OF THE MATERIAL IN THE FILTRATE IS EQUAL TO THAT IN THE PLASMA. D. AUTOREGULATION: 1. Most orgns re cpble of regulting their blood flow, independent of ny externl neurl or hormonl controls. This process is referred to s AUTOREGULATION. 2. In the kidney, there re two mechnisms of utoregultion. They generlly work together: Excretion by the vertebrte kidney: Clernce 5
6 . Myogenic mechnism: When rteril pressure rises (such s in the fferent rteriole), vsculr smooth muscle contrcts s it stretches. This increses resistnce of the rteriole thereby lowering the pressure nd flow through the glomerulus. As the renl blood flow (RBF) is lowered, the glomerulr filtrtion rte (GFR) is lso reduced. Thus high pressure will not result in proportiontely high rtes of urine production. Likewise, s pressure drops, rterioles will relx, R will decrese, P is reduced less nd Q remins high. The rte of urine production remins high even while the blood pressure is somewht reduced. b. TUBULOGLOMMERULAR FEEDBACK: Flow of fluid (or some solute in the fluid) through the glomerulus is sensed by cells tht mke up the JUXTAGLOMMERULAR APPARATUS. Their exct identity(ies) re not known. Nor is the exct mens by which they communicte with the smooth muscle cells of the fferent nd efferent glomerulr rterioles. It could be the renin- ngiotensin system (these cells produce renin), brdykinin, ctecholmines, or prostglndins. Nevertheless the results re well known: 1. If the GFR drops, the efferent rteriole dimeter decreses, this increses resistnce nd cuses n increse in the glomerulr cpillry, thereby incresing the GFR. 2. By contrst, if the GFR gets too high, then efferent rteriole pressure decreses nd filtrtion drops. Here is grph of the overll pttern of utoregultion: Flow Rte blood flow filtrtion rte Perfusion Pressure? Wht things re controlled to chieve reltively constnt GFR? Why is reltively constnt GFR desirble? III. TUBULAR SECRETION AND ABSORPTION MECHANISMS A. A lrge number of substnces re bsorbed from the filtrte or secreted into it by the cells lining the Proximl nd Distl Convoluted Tubules. 1. We will not consider (t this point) which substnces re moved t wht rtes nd where. We insted will be concerned with generl mechnisms. 2. In generl, ll mechnisms of re- bsorption nd secretion will involve some sort of protein meditor nd therefore ll of these processes re potentilly SATURABLE.. Therefore, we cn chrcterize ech trnsport protein in terms of its K m nd V mx. Recll tht: Excretion by the vertebrte kidney: Clernce 6
7 b. K m is lrgely mesure of ffinity between the crrier protein nd its substrte nd is set by its prticulr structure nd the physicl- chemicl environment. c. The V mx is lrgely determined by the totl number of trnsport proteins tht re vilble (nd lso their individul kinetics). Obviously, the more trnsport molecules tht re vilble, the higher the potentil rte of trnsport. 3. The ctul crriers themselves cn be divided into different clsses, lrgely ccording to the type of mterils they trnsport nd the mechnism they use. B. PATTERNS OF SECRETION AND RE- ABSORPTION 1. The most bsic grphicl tretment of secretion nd rebsorption is done by plotting the EXCRETORY RATE (usully in mount of mteril/time) vs. the PLASMA CONCENTRATION (in mount/vol.). There re severl other types of useful grphs; we will discuss ech t pproprite times. 2. GRAPHS OF DIFFERENT PROCESSES:. FILTRATION ONLY: If mteril is only filtered, there will be direct reltionship between the plsm concentrtion of the substnce nd the mount removed (lso referred to s the mount CLEARED): Filtrtion Rte Plsm Concentrtion b. Wht will hppen if substnce is being rebsorbed by the tubules? An exmple would be glucose. 1. The substnce (we'll tlk bout glucose) is filtered in wy tht would give curve identicl to the one shown bove. 2. When it enters the proximl convoluted tubule, there re mny glucose trnsport proteins locted on the inner wll of the tubules tht trnsport glucose out of the tubule. Thus, we hve two processes tht re tking plce in the body: one in glomerulus tht results in glucose getting in the filtrte in proportion to its plsm concentrtion nd the other tht trnsports glucose out of the tubule bck into the blood ccording to the K m nd V mx of the trnsport mechnism: Excretion by the vertebrte kidney: Clernce 7
8 Filtrtion Rte Rebsorption Rte Plsm Concentrtion Filtrte Glucose Concentrtion 3. The summed process is shown below. The removl of glucose results in decresed [glucose] in the filtrte. Excretion Rte predicted line, filtrtion only ctul line Plsm Concentrtion (mg glucose / dl). The removl mechnism is so effective tht t low plsm [glucose] (< ~180 mg/dl), no glucose is ctully excreted even though there is bundnt glucose in the filtrte. b. Eventully concentrtion is reched where the mount of glucose in the tubules is so high tht it overwhelms the trnsport mechnisms. 1. The point where this first strts to hppen is clled the RENAL THRESHOLD nd the concentrtion where V mx is reched is clled the TUBULAR MAXIMUM or T m. 2. Above the T m, the rte of excretion chnges the sme s the rte of filtrtion: however there is difference between the filtrtion nd ctul filtrte concentrtion tht equls the mount clered by filtrtion - the mount rebsorbed. Excretion by the vertebrte kidney: Clernce 8
9 3. In the re between the T m nd the renl threshold, the concentrtion of the mteril in the filtrte chnges t different rte thn fter the T m. This is clled SPLAY. The reson for the sply is obvious from n inspection of the re- bsorption grph shown previously. Glucose Excretion Excretion Rte sply Renl Threshold T m Plsm Concentrtion (mg glucose / dl)? If the K m of the trnsporter is gretly incresed wht would it men in terms of glucose remining in the filtrte t vrious concentrtions? Wht if the totl number of trnsporter proteins incresed? Wht would hppen to V mx nd the glucose tht ws being excreted? Drw grphs to explin your nswer. c. Wht hppens when substnce is ctively being SECRETED from the blood into the filtrte? If the substnce is lso being filtered, the process is identicl to tht of rebsorption shown bove EXCEPT tht now the TRANSPORT CURVE IS ADDED TO THE FILTRATION CURVE: Excretion by the vertebrte kidney: Clernce 9
10 filtrtion + secretion Excretion Rte predicted line, filtrtion only Plsm Concentrtion? If the substnce is not filtered nd is only secreted, wht would the excretion curve (mount clered/min vs. plsm conc.) look like? Wht is the bsis for your nswer? IV. THE CONCEPT OF CLEARANCE: A. Clernce cn be thought of s the removl of substnce from the blood (nd the body). Let's first consider the possible things tht cn hppen to some substnce (glucose for exmple) when it rrives t the kidney. 1. There is one venue of entry - - the plsm of the renl rtery nd therefore the mount tht enters will be the product of the renl rteril plsm flow, RPF nd the renl rteril plsm concentrtion of the substnce (let's cll it substnce x), P x. Thus: 1. Rte Substnce rrives t kidney = Px * RPF 2. There re two possible venues of exit from the kidney, the renl vein nd/or the ureter.. Exit through the renl vein cn be clculted in mnner similr to tht which enters vi the renl rtery, it will be the product of the concentrtion of x nd the renl vein plsm flow: 2. Rte substnce leves vi the renl veins = v Px * RPF v Excretion by the vertebrte kidney: Clernce 10
11 b. Exit vi the urine into the ureter will be clculted in similr mnner, in this cse the product of the rte of urine flow, V 1, nd the concentrtion of the substnce in the urine U x. 3. RATE EXCRETED = U x * V Thus: 4. P * RPF P v v x = x * RPF + ( Ux * V) This represents complete description of the hndling of ny substnce by the kidney. B. Renl physiologists use the notion of clernce to men totlly removing something from the blood. If something is completely clered, then ll of it leves the kidney vi the ureter nd none vi the renl veins; RPF v = 0. Rerrnging eq. 4 nd mking this substitution, we find 5. U * V P x = x * RPF -P v x * RPF = Px * RPF -0 * RPF Ux * V = P x * RPF v v this eqution expresses the equlity between the mount of substnce entering the kidneys in the renl rtery plsm nd tht leving in the urine. If we now define the clernce rte s the volume of renl rtery plsm per time needed to ccount for ll of the substnce found in the urine, then, rerrnging eqution #5 we find: 5. Clernce x = RPF = Ux * V Px where clernce hs the sme units s the renl plsm flow (usully ml*min - 1 in humn physiology).? As you know, in norml individuls, no glucose is lost in the urine. Although quite bit goes through the glomerulr filter, 100% is reclimed by trnsport in the proximl convoluted tubule nd therefore RPF = RPF v nd U x = 0. Wht is the clernce of glucose in ml/min? ANS: in norml individul it is zero none of the glucose is removed from the body by the kidney. We will further explore this concept in the next set of notes. Vo 1 This should relly be symbolized s since it is rte, but for resons unknown to be renl physiologists do not use this notion. So in renl phys., V is volume per time! Excretion by the vertebrte kidney: Clernce 11
Check your understanding 3
1 Wht is the difference etween pssive trnsport nd ctive trnsport? Pssive trnsport is the movement of prticles not requiring energy. Movement of prticles in ctive trnsport uses energy. 2 A gs tp in the
More informationCLEARANCE AND REABSORPTION OF WATER*
CLEARANCE AND REABSORPTION OF WATER* I. Glomerular Filtration Rate and Renal Plasma Flow A. It would be extremely useful for both practical and theoretical reasons to be able to estimate the amount of
More informationUrinary Physiology. Chapter 17 Outline. Kidney Function. Chapter 17
Urinary Physiology Chapter 17 Chapter 17 Outline Structure and Function of the Kidney Glomerular Filtration Reabsorption of Salt and Water Renal Plasma Clearance Renal Control of Electrolyte and Acid-Base
More informationBCH 450 Biochemistry of Specialized Tissues
BCH 450 Biochemistry of Specialized Tissues VII. Renal Structure, Function & Regulation Kidney Function 1. Regulate Extracellular fluid (ECF) (plasma and interstitial fluid) through formation of urine.
More informationHuman Urogenital System 26-1
Human Urogenital System 26-1 Urogenital System Functions Filtering of blood, Removal of wastes and metabolites Regulation of blood volume and composition concentration of blood solutes ph of extracellular
More informationP215 Spring 2018: Renal Physiology Chapter 18: pp , Chapter 19: pp ,
P215 Spring 2018: Renal Physiology Chapter 18: pp. 504-520, 525-527 Chapter 19: pp. 532-548, 553-560 I. Main Components of the Renal System 1. kidneys 2. ureters 3. urinary bladder 4. urethra 4 Major Functions
More informationMAJOR FUNCTIONS OF THE KIDNEY
MAJOR FUNCTIONS OF THE KIDNEY REGULATION OF BODY FLUID VOLUME REGULATION OF OSMOTIC BALANCE REGULATION OF ELECTROLYTE COMPOSITION REGULATION OF ACID-BASE BALANCE REGULATION OF BLOOD PRESSURE ERYTHROPOIESIS
More informationNovember 30, 2016 & URINE FORMATION
& URINE FORMATION REVIEW! Urinary/Renal System 200 litres of blood are filtered daily by the kidneys Usable material: reabsorbed back into blood Waste: drained into the bladder away from the heart to the
More informationVertebrates possess kidneys: internal organs which are vital to ion and water balance and excretion.
The Kidney Vertebrates possess kidneys: internal organs which are vital to ion and water balance and excretion. The kidney has 6 roles in the maintenance of homeostasis. 6 Main Functions 1. Ion Balance
More informationExcretion Chapter 29. The Mammalian Excretory System consists of. The Kidney. The Nephron: the basic unit of the kidney.
Excretion Chapter 29 The Mammalian Excretory System consists of The Kidney 1. Vertebrate kidneys perform A. Ion balance B. Osmotic balance C. Blood pressure D. ph balance E. Excretion F. Hormone production
More informationRenal System and Excretion
Renal System and Excretion Biology 105 Lecture 19 Chapter 16 Outline Renal System I. Functions II. Organs of the renal system III. Kidneys 1. Structure 2. Function IV. Nephron 1. Structure 2. Function
More informationSunday, July 17, 2011 URINARY SYSTEM
URINARY SYSTEM URINARY SYSTEM Let s take a look at the anatomy first! KIDNEYS: are complex reprocessing centers where blood is filtered through and waste products are removed. Wastes and extra water become
More informationRENAL PHYSIOLOGY, HOMEOSTASIS OF FLUID COMPARTMENTS (1)
RENAL PHYSIOLOGY, HOMEOSTASIS OF FLUID COMPARTMENTS (1) Dr. Attila Nagy 2017 Functional role of the kidney 1.Homeostasis of fluid compartments (isosmia, isovolemia, isoionia, isohydria,) 2. Elimination
More information014 Chapter 14 Created: 9:25:14 PM CST
014 Chapter 14 Created: 9:25:14 PM CST Student: 1. Functions of the kidneys include A. the regulation of body salt and water balance. B. hydrogen ion homeostasis. C. the regulation of blood glucose concentration.
More informationRNPDC CCNP Anatomy and Physiology: Renal System Pre-Quiz 2015
RNPDC CCNP Anatomy and Physiology: Renal System Pre-Quiz 2015 1. In which abdominal cavity do the kidneys lie? a) Peritoneum. b) Anteperitoneal. c) Retroperitoneal. d) Parietal peritoneal 2. What is the
More informationHuman Physiology - Problem Drill 17: The Kidneys and Nephronal Physiology
Human Physiology - Problem Drill 17: The Kidneys and Nephronal Physiology Question No. 1 of 10 Instructions: (1) Read the problem statement and answer choices carefully, (2) Work the problems on paper
More informationRenal Functions: Renal Functions: Renal Function: Produce Urine
Renal Functions: Excrete metabolic waste products Reabsorb vital nutrients Regulate osmolarity: Maintain ion balance Regulate extracellular fluid volume (and thus blood pressure) Renal Functions: Regulate
More informationBIOH122 Human Biological Science 2
BIOH122 Human Biological Science 2 Session 16 Urinary System 1 The Kidneys Bioscience Department Endeavour College of Natural Health endeavour.edu.au Session Plan o Functions of Urinary system o The Kidneys:
More informationEXCRETORY SYSTEM E. F. G. H.
XRTORY SYSTM 1. Label the following parts of the nephron in the diagram below:..... F. G. H. I. J. K. L. 2. Identify the following as either True or False: There is a greater osmotic concentration in the
More informationIntroduction to the kidney: regulation of sodium & glucose. Dr Nick Ashton Senior Lecturer in Renal Physiology Faculty of Biology, Medicine & Health
Introduction to the kidney: regulation of sodium & glucose Dr Nick Ashton Senior Lecturer in Renal Physiology Faculty of Biology, Medicine & Health Objectives Overview of kidney structure & function Glomerular
More informationOutline Urinary System
Urinary System and Excretion Bio105 Lecture Packet 20 Chapter 16 Outline Urinary System I. Function II. Organs of the urinary system A. Kidneys 1. Function 2. Structure B. Urine formation 1. Hormonal regulation
More informationA. Incorrect! The urinary system is involved in the regulation of blood ph. B. Correct! The urinary system is involved in the synthesis of vitamin D.
Human Anatomy - Problem Drill 22: The Urinary System Question No. 1 of 10 1. Which of the following statements about the functions of the urinary system is not correct? Question #01 (A) The urinary system
More informationUnit #4 Waste and Excretion. The Kidneys
Unit #4 Waste and Excretion The Kidneys Renal Hilus (Hilus) the doorway of the kidney Ureter leaves this region blood and lymphatic vessels enter and exit here Renal Capsule (Capsule) smooth fibrous tissue
More informationLECTURE 25: FILTRATION AND CLEARANCE NEPHRON FILTRATION
LECTURE 25: FILTRATION AND CLEARANCE NEPHRON FILTRATION 1. Everything in the plasma is filtered except large proteins and red blood cells. The filtrate in Bowman s capsule is an isosmotic fluid that is
More informationNephron Function and Urine Formation. Ms. Kula December 1, 2014 Biology 30S
Nephron Function and Urine Formation Ms. Kula December 1, 2014 Biology 30S The Role of the Nephron In order for the body to properly function and maintain homeostasis, the amount of dissolved substances
More informationUrinary System and Excretion. Bio105 Lecture 20 Chapter 16
Urinary System and Excretion Bio105 Lecture 20 Chapter 16 1 Outline Urinary System I. Function II. Organs of the urinary system A. Kidneys 1. Function 2. Structure III. Disorders of the urinary system
More informationBasic Functions of the Kidneys
Dr. Adelina Vlad Basic Functions of the Kidneys Eliminate plasma METABOLIC WASTE PRODUCTS and FOREIGN COMPOUNDS The kidney are the primary means for eliminating metabolic waste products (urea, creatinine,
More informationChapter 25 The Urinary System
Chapter 25 The Urinary System 10/30/2013 MDufilho 1 Kidney Functions Removal of toxins, metabolic wastes, and excess ions from the blood Regulation of blood volume, chemical composition, and ph Gluconeogenesis
More informationThe functions of the kidney:
The functions of the kidney: After reading this lecture you should be able to.. 1. List the main functions of the kidney. 2. Know the basic physiological anatomy of the kidney and the nephron 3. Describe
More informationBIPN100 F15 Human Physiology (Kristan) Problem Set #8 Solutions p. 1
BIPN100 F15 Human Physiology (Kristan) Problem Set #8 Solutions p. 1 1. a. Proximal tubule. b. Proximal tubule. c. Glomerular endothelial fenestrae, filtration slits between podocytes of Bowman's capsule.
More informationLab Activity 31. Anatomy of the Urinary System. Portland Community College BI 233
Lab Activity 31 Anatomy of the Urinary System Portland Community College BI 233 Urinary System Organs Kidneys Urinary bladder: provides a temporary storage reservoir for urine Paired ureters: transport
More informationPHGY210 Renal Physiology
PHGY210 Renal Physiology Tomoko Takano, MD, PhD *Associate Professor of Medicine and Physiology McGill University *Nephrologist, McGill University Health Centre Lecture plan Lecture 1: Anatomy, basics
More informationOutline Urinary System. Urinary System and Excretion. Urine. Urinary System. I. Function II. Organs of the urinary system
Outline Urinary System Urinary System and Excretion Bio105 Chapter 16 Renal will be on the Final only. I. Function II. Organs of the urinary system A. Kidneys 1. Function 2. Structure III. Disorders of
More informationUrinary System Organization. Urinary System Organization. The Kidneys. The Components of the Urinary System
Urinary System Organization The Golden Rule: The Job of The Urinary System is to Maintain the Composition and Volume of ECF remember this & all else will fall in place! Functions of the Urinary System
More informationChapter 23. The Nephron. (functional unit of the kidney
Chapter 23 The Nephron (functional unit of the kidney Renal capsule The Nephron Renal cortex Nephron Collecting duct Efferent arteriole Afferent arteriole (a) Renal corpuscle: Glomerular capsule Glomerulus
More informationExcretion and Waste Management. Biology 30S - Miss Paslawski
Excretion and Waste Management Biology 30S - Miss Paslawski Lesson 1 Waste Products and Organs 2 3 Excretion Excretion: Process by which dissolved metabolic wastes are separated from body fluids and removed
More information1. a)label the parts indicated above and give one function for structures Y and Z
Excretory System 1 1. Excretory System a)label the parts indicated above and give one function for structures Y and Z W- renal cortex - X- renal medulla Y- renal pelvis collecting center of urine and then
More informationBIOLOGY - CLUTCH CH.44 - OSMOREGULATION AND EXCRETION.
!! www.clutchprep.com Osmoregulation regulation of solute balance and water loss to maintain homeostasis of water content Excretion process of eliminating waste from the body, like nitrogenous waste Kidney
More informationOsmotic Regulation and the Urinary System. Chapter 50
Osmotic Regulation and the Urinary System Chapter 50 Challenge Questions Indicate the areas of the nephron that the following hormones target, and describe when and how the hormones elicit their actions.
More informationChapter 25: Urinary System
Chapter 25: Urinary System I. Kidney anatomy: retroperitoneal from 12 th thoracic to 3 rd lumbar area A. External anatomy: hilus is the indentation 1. Adrenal gland: in the fat at the superior end of each
More informationRENAL PHYSIOLOGY DR.CHARUSHILA RUKADIKAR ASSISTANT PROFESSOR PHYSIOLOGY
RENAL PHYSIOLOGY DR.CHARUSHILA RUKADIKAR ASSISTANT PROFESSOR PHYSIOLOGY GROSS ANATOMY Location *Bean-shaped *Retroperitoneal *At level of T12 L1 vertebrae. *The right kidney lies slightly inferior to left
More informationUrinary System. consists of the kidneys, ureters, urinary bladder and urethra
Urinary System 1 Urinary System consists of the kidneys, ureters, urinary bladder and urethra 2 Location of Kidneys The kidneys which are positioned retroperitoneally lie on either side of the vertebral
More informationOsmoregulation and Renal Function
1 Bio 236 Lab: Osmoregulation and Renal Function Fig. 1: Kidney Anatomy Fig. 2: Renal Nephron The kidneys are paired structures that lie within the posterior abdominal cavity close to the spine. Each kidney
More informationAnatomy/Physiology Study Guide: Unit 9 Excretory System
Anatomy/Physiology Study Guide: Unit 9 Excretory System 1) In the space below, list the primary structures (organs) and their corresponding functions. Structures: Functions: KIDNEY 1) URETER BLADDER URETHRA
More informationFifth Year Biology. Excretion. Miss Rochford
Fifth Year Biology Excretion Miss Rochford In this Topic Excretion in plants Excretion and homeostasis Skin Organs of excretion Urinary system Kidneys Nephron Control of urine volume Characteristics of
More informationBody fluid volume is small (~5L (blood + serum)) Composition can change rapidly e.g. due to increase in metabolic rate
Renal physiology The kidneys Allow us to live on dry land. Body fluid volume is small (~5L (blood + serum)) Composition can change rapidly e.g. due to increase in metabolic rate Kidneys maintain composition
More informationFunctions of the kidney
Physiology of Urinary tract Kidney, Ureter, Urinary bladder Urethra Kidney function Excretion Physiology of volume regulation Functions of the kidney Excretion of dangerous substances endogenous (metabolites):
More information2) This is a Point and Click question. You must click on the required structure.
Class: A&P2-1 Description: Test: Excretory Test Points: 144 Test Number: 28379 Printed: 31-March-10 12:03 1) This is a Point and Click question. You must click on the required structure. Click on the Bowman's
More informationAP2, Lab 7 - THE URINARY SYSTEM
AP2, Lab 7 - THE URINARY SYSTEM I. SYSTEM COMPONENTS (Figs. 25.1 25.4) KIDNEYS Each kidney contains approx. 1,000,000 tubular NEPHRONS which produce FILTRATE from the plasma and then add to or take from
More informationExcretory Lecture Test Questions Set 1
Excretory Lecture Test Questions Set 1 1. The separation and ejection of metabolic wastes, usually in aqueous solution, is: a. reabsorption b. secretion c. filtration d. excretion e. endocrinology 2. Besides
More informationQUIZ/TEST REVIEW NOTES SECTION 1 RENAL PHYSIOLOGY FILTRATION [THE KIDNEYS/URINARY SYSTEM] CHAPTER 19 CHAPTER 19
QUIZ/TEST REVIEW NOTES SECTION 1 RENAL PHYSIOLOGY FILTRATION [THE KIDNEYS/URINARY SYSTEM] CHAPTER 19 CHAPTER 19 Learning Objectives: Differentiate the following processes: filtration, reabsorption, secretion,
More information19. RENAL PHYSIOLOGY ROLE OF THE URINARY SYSTEM THE URINARY SYSTEM. Components and function. V BS 122 Physiology II 151 Class of 2011
19. RENAL PHYSIOLOGY THE URINARY SYSTEM Components and function The urinary system is composed of two kidneys, the functionally filtering apparatus, which connect through two tubular structures called
More informationBy: Dr. Foadoddini Department of Physiology & Pharmacology Birjand University of Medical Sciences. Body fluids and.
By: Dr. Foadoddini Department of Physiology & Pharmacology Birjand University of Medical Sciences Body fluids and Renal physiology 25 Volume and Osmolality of Extracellular and Intracellular Fluids
More informationThe Excretory System. Biology 20
The Excretory System Biology 20 Introduction Follow along on page 376 What dangers exist if your body is unable to regulate the fluid balance of your tissues? What challenged would the body have to respond
More informationCopyright 2009 Pearson Education, Inc. Copyright 2009 Pearson Education, Inc. Figure 19-1c. Efferent arteriole. Juxtaglomerular apparatus
/6/0 About this Chapter Functions of the Kidneys Anatomy of the urinary system Overview of kidney function Secretion Micturition Regulation of extracellular fluid volume and blood pressure Regulation of
More informationHuman Anatomy and Physiology - Problem Drill 23: The Urinary System, Fluid, Electrolyte and Acid-Base Balance
Human Anatomy and Physiology - Problem Drill 23: The Urinary System, Fluid, Electrolyte and Acid-Base Balance Question No. 1 of 10 Which of the following statements about the functions of the urinary system
More informationCHAPTER 25 URINARY. Urinary system. Kidneys 2 Ureters 2 Urinary Bladder 1 Urethra 1. functions
CHAPTER 25 URINARY Kidneys 2 Ureters 2 Urinary Bladder 1 Urethra 1 fluid waste elimination secretion of wastes control blood volume and BP control blood ph electrolyte levels RBC levels hormone production
More informationPARTS OF THE URINARY SYSTEM
EXCRETORY SYSTEM Excretory System How does the excretory system maintain homeostasis? It regulates heat, water, salt, acid-base concentrations and metabolite concentrations 1 ORGANS OF EXCRETION Skin and
More informationNephron Anatomy Nephron Anatomy
Kidney Functions: (Eckert 14-17) Mammalian Kidney -Paired -1% body mass -20% blood flow (Eckert 14-17) -Osmoregulation -Blood volume regulation -Maintain proper ion concentrations -Dispose of metabolic
More informationRenal Quiz - June 22, 21001
Renal Quiz - June 22, 21001 1. The molecular weight of calcium is 40 and chloride is 36. How many milligrams of CaCl 2 is required to give 2 meq of calcium? a) 40 b) 72 c) 112 d) 224 2. The extracellular
More informationdescribe the location of the kidneys relative to the vertebral column:
Basic A & P II Dr. L. Bacha Chapter Outline (Martini & Nath 2010) list the three major functions of the urinary system: by examining Fig. 24-1, list the organs of the urinary system: describe the location
More informationThe kidneys are excretory and regulatory organs. By
exercise 9 Renal System Physiology Objectives 1. To define nephron, renal corpuscle, renal tubule, afferent arteriole, glomerular filtration, efferent arteriole, aldosterone, ADH, and reabsorption 2. To
More informationKidney Functions Removal of toxins, metabolic wastes, and excess ions from the blood Regulation of blood volume, chemical composition, and ph
The Urinary System Urinary System Organs Kidneys are major excretory organs Urinary bladder is the temporary storage reservoir for urine Ureters transport urine from the kidneys to the bladder Urethra
More informationNephron Structure inside Kidney:
In-Depth on Kidney Nephron Structure inside Kidney: - Each nephron has two capillary regions in close proximity to the nephron tubule, the first capillary bed for fluid exchange is called the glomerulus,
More informationorgans of the urinary system
organs of the urinary system Kidneys (2) bean-shaped, fist-sized organ where urine is formed. Lie on either sides of the vertebral column, in a depression beneath peritoneum and protected by lower ribs
More informationRENAL PHYSIOLOGY, HOMEOSTASIS OF FLUID COMPARTMENTS (1)
RENAL PHYSIOLOGY, HOMEOSTASIS OF FLUID COMPARTMENTS (1) Dr. Attila Nagy 2017 Functional roles of the kidney 1.Homeostasis of fluid compartments (isosmia, isovolemia, isoionia, isohydria,) 2. Elimination
More informationLesson 14.1: Learning the Key Terms
209 Lesson 14.1: Learning the Key Terms Directions: Place the letter of the best definition next to each key term. 1. collecting duct 2. distal convoluted tubule 3. glomerulus 4. nephron 5. nephron loop
More informationURINARY SYSTEM. These organs lie posterior or inferior to the. (membrane).
URINARY SYSTEM I. INTRODUCTION Each kidney is made up of about a million tiny tubules called nephrons. Each nephron individually filters the blood and makes urine and it does the job completely, from start
More informationKD02 [Mar96] [Feb12] Which has the greatest renal clearance? A. PAH B. Glucose C. Urea D. Water E. Inulin
Renal Physiology MCQ KD01 [Mar96] [Apr01] Renal blood flow is dependent on: A. Juxtaglomerular apparatus B. [Na+] at macula densa C. Afferent vasodilatation D. Arterial pressure (poorly worded/recalled
More informationRenal-Related Questions
Renal-Related Questions 1) List the major segments of the nephron and for each segment describe in a single sentence what happens to sodium there. (10 points). 2) a) Describe the handling by the nephron
More informationQuestion 1: Solution 1: Question 2: Question 3: Question 4: Class X The Excretory System Biology
A. MULTIPLE CHOICE TYPE: (select the most appropriate option in each case) Book Name: Selina Concise Question 1: Excretion primarily involves (a) removal of all byproducts during catabolism (b) removal
More informationGlomerular Capillary Blood Pressure
Glomerular Capillary Blood Pressure Fluid pressure exerted by blood within glomerular capillaries Depends on Contraction of the heart Resistance to blood flow offered by afferent and efferent arterioles
More informationGeneral Anatomy of Urinary System
General Anatomy of Urinary System URINARY SYSTEM ORGANS Kidneys (2) Ureters (2) Urinary bladder Urethra KIDNEY FUNCTIONS Control blood volume and composition KIDNEY FUNCTIONS Filter blood plasma, eliminate
More informationRENAL PHYSIOLOGY. Physiology Unit 4
RENAL PHYSIOLOGY Physiology Unit 4 Renal Functions Primary Function is to regulate the chemistry of plasma through urine formation Additional Functions Regulate concentration of waste products Regulate
More information5.Which part of the nephron removes water, ions and nutrients from the blood?
Uro question 1.While reading a blood test I notice a high level of creatinine, I could assume from this that A) There is a possibility of a UTI B) There is a possibility of diabetes C) There is a possibility
More information1. Urinary System, General
S T U D Y G U I D E 16 1. Urinary System, General a. Label the figure by placing the numbers of the structures in the spaces by the correct labels. 7 Aorta 6 Kidney 8 Ureter 2 Inferior vena cava 4 Renal
More informationUrinary System Laboratory
Urinary System Laboratory 1 Adrenal gland Organs of The Urinary System Renal artery and vein Kidney Ureter Urinary bladder Figure 26.1 2 Urethra Functions of the urinary system organs: Urethra expels urine
More informationOne Minute Movies: Molecular Action at the Nephron Joy Killough / Westwood High School / Austin,TX
One Minute Movies: Molecular Action at the Nephron Joy Killough / Westwood High School / Austin,TX To prepare your nephron model: ( A nephron is a tubule and the glomerulus. There are about a million of
More informationUrinary bladder provides a temporary storage reservoir for urine
Urinary System Organs Kidney Filters blood, allowing toxins, metabolic wastes, and excess ions to leave the body in urine Urinary bladder provides a temporary storage reservoir for urine Paired ureters
More informationURINARY SYSTEM. Primary functions. Major organs & structures
URINARY SYSTEM Primary functions Excretion of metabolic wastes Regulation of water and ion balances Regulation of blood pressure Vitamin D activation Regulation of rbc s (erythropoietin) Gluconeogenesis
More informationFunctional morphology of kidneys Clearance
Functional morphology of kidneys Clearance Assoc. Prof. MUDr. Markéta Bébarová, Ph.D. Department of Physiology Faculty of Medicine, Masaryk University This presentation includes only the most important
More informationThe Urinary System 15PART A. PowerPoint Lecture Slide Presentation by Patty Bostwick-Taylor, Florence-Darlington Technical College
PowerPoint Lecture Slide Presentation by Patty Bostwick-Taylor, Florence-Darlington Technical College The Urinary System 15PART A Functions of the Urinary System Elimination of waste products Nitrogenous
More informationExcretory System 1. a)label the parts indicated above and give one function for structures Y and Z
Excretory System 1 1. Excretory System a)label the parts indicated above and give one function for structures Y and Z W- X- Y- Z- b) Which of the following is not a function of the organ shown? A. to produce
More informationHistology Urinary system
Histology Urinary system Urinary system Composed of two kidneys, two ureters, the urinary bladder, and the urethra, the urinary system plays a critical role in: 1- Blood filtration,(filtration of cellular
More informationYou only get to change two things: the cardiac output and the resistance of the vasculature
Vsculr Biology 3 Regultion of Flow nd Pressure A. Arteril Pressure (oeriew) 1. Arteril pressure pulse 2. Men rteril pressure 2 MAP 1 P + s P 3 3 d MAP = men rteril pressure, P s = systolic pressure, P
More informationKidney and urine formation
Kidney and urine formation Renal structure & function Urine formation Urinary y concentration and dilution Regulation of urine formation 1 Kidney and urine formation 1.Renal structure & function 1)General
More informationPhysio 12 -Summer 02 - Renal Physiology - Page 1
Physiology 12 Kidney and Fluid regulation Guyton Ch 20, 21,22,23 Roles of the Kidney Regulation of body fluid osmolarity and electrolytes Regulation of acid-base balance (ph) Excretion of natural wastes
More informationQuestions? Homework due in lab 6. PreLab #6 HW 15 & 16 (follow directions, 6 points!)
Questions? Homework due in lab 6 PreLab #6 HW 15 & 16 (follow directions, 6 points!) Part 3 Variations in Urine Formation Composition varies Fluid volume Solute concentration Variations in Urine Formation
More informationI. Metabolic Wastes Metabolic Waste:
I. Metabolic Wastes Metabolic Waste: a) Carbon Dioxide: by-product of cellular respiration. b) Water: by-product of cellular respiration & dehydration synthesis reactions. c) Inorganic Salts: by-product
More informationCollin County Community College RENAL PHYSIOLOGY
Collin County Community College BIOL. 2402 Anatomy & Physiology WEEK 12 Urinary System 1 RENAL PHYSIOLOGY Glomerular Filtration Filtration process that occurs in Bowman s Capsule Blood is filtered and
More informationChapter 24: The Urinary System
Chapter 24: The Urinary System Overview of kidney functions n Regulation of blood ionic composition n Regulation of blood ph n Regulation of blood volume n Regulation of blood pressure n Maintenance of
More informationChapter 12. Excretion and the Interaction of Systems
Chapter 12 Excretion and the Interaction of Systems 1 2 Goals for This Chapter 1. Identify the main structures and functions of the human excretory system 2. Explain the function of the nephron 3. Describe
More informationRENAL SYSTEM 2 TRANSPORT PROPERTIES OF NEPHRON SEGMENTS Emma Jakoi, Ph.D.
RENAL SYSTEM 2 TRANSPORT PROPERTIES OF NEPHRON SEGMENTS Emma Jakoi, Ph.D. Learning Objectives 1. Identify the region of the renal tubule in which reabsorption and secretion occur. 2. Describe the cellular
More informationBiology Slide 1 of 36
Biology 1 of 36 38 3 The Excretory System 2 of 36 Functions of the Excretory System 1.Function: process which eliminates metabolic wastes 3 of 36 Functions of the Excretory System (The skin excretes excess
More informationUrinary system. Urinary system
INTRODUCTION. Several organs system Produce urine and excrete it from the body Maintenance of homeostasis. Components. two kidneys, produce urine; two ureters, carry urine to single urinary bladder for
More informationClass XI - Biology Excretory Products and their Elimination
Class XI - Biology Excretory Products and their Elimination MULTIPLE CHOICE QUESTIONS 1. The following substances are the excretory products in animals. Choose the least toxic form among them? a. Urea
More informationClass XI Chapter 19 Excretory Products and their Elimination Biology
Class XI Chapter 19 Excretory Products and their Elimination Biology Question 1: Define Glomerular Filtration Rate (GFR) Glomerular filtration rate is the amount of glomerular filtrate formed in all the
More informationUrinary System. Dr. Ahmed Maher Dr. Ahmed Manhal
Urinary System Dr. Ahmed Maher Dr. Ahmed Manhal Presentation Map Kidney (cortex & medulla). Nephron. Duct system. Juxtaglomerular apparatus. Ureter, bladder & urethra. Definition & General Structure The
More informationFigure 26.1 An Introduction to the Urinary System
Chapter 26 Figure 26.1 An Introduction to the Urinary System Components of the Urinary System Kidney Produces urine Ureter Transports urine toward the urinary bladder Urinary Bladder Temporarily stores
More information