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192 Cards in this Set
- Front
- Back
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What three things does cell function depend on |
continuous nutrient supply removal of metabolic end products homeostasis of ECF |
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What modifies ECF substance concentration? |
internal and external changes |
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what are the 4 sites water is lost to |
skin lungs GI tract and kidneys |
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what sites are insensible losses |
skinand lungs |
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what 2 processes maintain water balance |
thirst and urinary tract |
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what is avg volume filtered into Bowmans capsule |
180L/day about 20 percent of total volume |
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what is average volume filtered through glomerulus |
900L/day |
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what does the setup of the kidney enable |
processing & excretion of large volumes of plasma and waste and precise regulation of constituents of internal environment |
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what are the 3 layers of the kidney |
cortex medulla/Renal Pyramid ( with uo to 18 pyramids) Renal Pelvis
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what structures are part of the renal pelvis |
renal artery vein and capsule, ureter and papille |
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what are the 2 main functions of the kidney |
excrete end products of metabolism and control concentration of constituents in bodily fluids |
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what 2 processes control composition and volume of the filtered plasma and what methos is used |
Secretion and reabsorption use active and passive transport |
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What is the Ureter |
the formtaion of all the tubules when joined; what urine is actually excreted through |
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what does the kidney regulate by altering blood plasma |
osmolality and solute composition of interstitial fluid |
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whats the function unit of the kidney |
the nephron, where urine is formed |
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what are the 2 main sections of the nephron |
glomerulus and renal tubule (proximal ends for a cup known as bowmans capsule) |
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what does the renal Capsule (not the renal tubules) consist of |
the bowmans capsule (AKA renal tubule) and the glomerulus; yields glomerular filtration |
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what are the 2 types of nephrons |
Juxtomedullary and cortical |
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describe the juxtomedullary nephron |
glomerulus close to corticoglomerular membrane & descending tubule reaches into inner medulla; only 1/7 of the nephrons are like this |
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describe the cortical nephrons |
glomerulus in outer cortical zone and descending tubules do not penetrate in to inner medulla; 7/8 of nephrons are like this |
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what are the 2 types of nephron components |
tubular and vascular |
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what is the list of tubular components |
bowmans capsule, proximal tubule, descending and ascending L.O.H. (thin and thick), distal tubule, collecting tubule, collecting duct which empties into the renal gland |
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What is the juxtoglomerular complex/aparatus |
the return of the distal tubule to near the glomerulus to allow for exchange yielding a form of autoregulation |
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does the cortical nephron reach the inner medulla |
NO the LOH only goes down to outer medulla |
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what are the two main Vascular components |
two capillary beds: glomerulus and peritubular capillaries |
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What is the pressure difference among the capillary beds |
glomerulus has high pressure while peritubular is low pressure bed |
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HOW ARE AFFERENT AND EFFERENT ARTERIOLES RELATED TO CAPILLARY BEDS |
AFFERENT ARTERIOLES BRING BLOOD TO GLOMERULUS WHILE BLOOD LEAVING GLOMERULUS IS CARRIED THROUGH PERITUBULAR CAPILARRIES BY EFFERENT ARTERIOLES |
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WHAT IS THE VASA RECTA |
PORTION OF PERITUBULAR CAPILLARY SYSTEM THAT DESCENDS AROUND THE LOH IN THE INNER/LOWER MEDULLLA; forms concentrated urine |
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What is the basic function of the nephron |
clear blood plasma of unwanted substances as pass through kidney |
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what are the 3 main mechanisms of the nephron |
Glomerular filtration, tubular reabsorption and tubular secretion |
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Describe glomerular filtration |
plasma and blood about 20% filtered through glomerular membrane |
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describe tubular reabsorption |
while filtered fluid flows, unwanted substances stay in tubules and wanted substances (H2O & electrolytes) reabsorped into peritubular capillaries |
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Describe tubular secretion |
unwanted substances not originally filtered into the bowmans capsule are secreted from peritubular capillaries directly into tubules through epithelial cell linings |
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What does Glomerular filtration consist of |
1st step in urine production where blood is forced through 3 layer glomerular membrane by glomerulus pressure; most proteins and large substances do not make it through process |
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name the three layers of the glomerular membrane |
capillary endothelial cell, basement membrane & epithelial cellls |
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What are the small pores of the capillary endothelial cell called
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fenestrae
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what can and cannot filter though the fenestre
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plasma proteins and small solutes pass though fenestrae but blood cells are restricted
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what cells are restricted from entering the basement membrane
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larger plasma proteins cannot pass thought the basement membrane
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which layer of the glomerular membrane lines the outer surface
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epithelial cells
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what can pass through the epithelial layer
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only molecules <7nm can pass though the slit pore openings of the epithelial layer
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Do glomerular membranes require energy to filter?
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No, there is no active transport, it all works through pressure differences
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Describe the pressure difference between the glomerulus and the bowman capsule
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hydrostatic pressure always higher in glomerulus than bowman capsule to push the filtrate through the membranes
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What is true about the filtrate contents after going through the membranes
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the fluid is protein free and all crystalloid; crystalloid concentration is equal to that of plasma
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**what crystalloids are found in bowman capsule fluid? |
H+, Cl-, K+, Na-, phosphate, urea, creatine, uric acid |
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what determines the effective (net) filtration pressure Peff of the glomerulus?
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Glomerular pressure Pg, colloid osmotic pressure in glomerular capillaries Po & pressure of the bowman capsule Pb
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what two forces oppose filtration?
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Colloid osmotic pressure and pressure of bowman capsule
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What force drives filtration and describe how it works
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Glomerular pressure ~60 mm Hg consists of pressure in glomerular capillaries that promote filtration through membrane
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what is colloid osmotic pressure?
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Pressure of venous end of glomerular capillaries ~ 32mm Hg Occurs because proteins concentration increases due to proteins not being passed through membrane; about 20 % increase of proteins in venous end therefore increase in pressure and opposes filtration
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Describe pressure of bowman capsule
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resistance of capsule wall and filtered fluid builds up opposing pressure to filtration ~15 mmHg
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What is the Peff Formula?
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Peff= Pg-(Po+Pb) = 60 -(32+18) = 10 mmHg
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What is glomerular filtration rate (GFR)
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GFR=Peff*Kf where Kf is the filtration coffee; normally GFR= 125 ml/min
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What happens to the oncotic pressure (colloid Pressure) of glomerulus as you move further along the capillary network?
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Po (pressure of the glomerular capillaries) willrise until there is no net pressure difference because more and more plasma is taken out along the way so Po keeps rising until there is no net difference
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Why can you consider Pob oncotic pressure of the bowman space to be 0
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because there are no proteins that filter into the bowman capsule
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Describe Po oncotic pressure and Peff as plasma flows toward efferent arterioles
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Po rises because more plasma is removed leaving a greater concentration of proteins in capillaries and Peff declines due to the rise in Po; there is a greater resistance therefore there is a decrease in net pressure
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Is hydrostatic pressure maintained along glomerular capillaries?
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yes but it falls in both afferent and efferent arterioles
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what is the determining factor in calculating GFR
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Peff because Kf (filtration coeff) doesn't change unless the kidney is damaged
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What factors influence Peff and therefore GFR
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renal blood flow, afferent and efferent arterial resistance, sympathetic stimulation, & arteriole pressure
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How does renal blood flow affect GFR
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increase rate of blood flow thereby increased Pg (glomerular pressure & decreasing Po oncotic pressure and increasing both Peff and GFR
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How does afferent and efferent arterial resistance affect GFR?
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GFR has an inverse relationship with the ratio of Ra to Re. If afferent resistance increases, ratio of afferent to efferent resistance increases thereby lowering GFR; If efferent resistance increases the ratio will decrease and GFR will increase
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what does constricting the afferent arteriole do
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decrease blood flow into glomerulus therefore decreasing Pg decreasing Peff and GFR
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What does sympathetic stimulation do to GFR
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sympathetic stimulation causes constriction of afferent arterioles and there fore decreases GFR
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How does arterial pressure affect GFR
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not much affect because if there is an increase in arterial pressure there will be a rise in Pg and auto regulation will take over and blunt the affects
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**what are two conditions altering Peff
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Glomerulonephritis and Annuria
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Describe glomerulonephritis
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glomerulus is hyperpermeable enabling proteins to filter through membranes causing an increase in bowman capsule oncotic pressure which was previously 0. This will then decrease Po capillary oncotic pressure which causes and increase in Peff GFR and urine output
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Describe Annuria
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Pg decreases due to a decrease in arterial pressure of inflamed glomeruli; this causes a decrease in Peff GFR and urine output
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Why is auto regulation important?
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So glomerular filtrate flows in tubules at an appropriate rate and unwanted stuff goes into the urine while wanted stuff gets reabsorbed
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what are the two hypothesis for how auto regulation occurs |
1. Smooth muscle senses an increase in arterial pressure and constricts to maintain Pg. 2. Macula Densa cells sense Na+in the distal tubule and signal afferent arteriole to constrict |
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What is the tubuloglomerular feedback system?
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combo of afferent and effect arteriolar feedback that occurs in the juxtaglomerular complex
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What is the juxtaglomerular complex
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region in the kidney cortex where auto regulation takes place (due to tubuloglomerular feedback); Think ascending LOH contacts afferent and efferent arterioles
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What 2 specialized epithelial cells enable juxtoglomerular complex to work
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juxtaglomerular cells adjacent to afferent and efferent arterioles and macula dense cells in distal tubule adjacent to arterioles
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How does afferent arteriole feedback system work |
Low GFR (because low pressure in arteries) causes an over reabsorption of Na+ and Cl- in ascending limb which causes a decrease in ion concentration in the macula densa cells which then signal the afferent dilation and yield an increase in blood flow, Pg, and GFR |
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how does the efferent arteriole feedback system work?
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Same as afferent except the decrease in ion concentration causes the juxtaglomerular cells to release renin which forms angiotensin1 and then 2 which constricts the efferent arteriole and causes a rise is Pg and GFR
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What is the third way macula dense cells regulate GFR |
creation of angiotensin 2 stimulates adrenal cortex to produce aldosterone which enhances Na+ and therefore H2O reabsorption by distal tubules thereby increasing ECF and the BP is restored |
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What is Clearance
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volume of blood plasma which have to be present at nephron to provide amount of solute actually found in urine
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what is the formula for clearance
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arterial output = venous output + urine output.
{Pa*RPFa}=[Pv*RPFv]+[U Vu] artery concentration of S * flowrate = vein concentration of S * flowrate + Urine concentration of S * urine flowrate |
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In calculation clearance what do we assume
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Kidney takes all substance S from arteries and excretes it through urine so venous output is 0
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What is final equation for clearance
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Cs=(U*Vu)/Pa=Eu/Pa => virtual volume of plasma that would be totally cleared of substance S in unit time
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Why would we use inline of creatinine to solve for clearance
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Because both substances are not reabsorbed or secreted so their Cs= GFR = 125ml/min
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How is clearance related to GFR reabsorption, secretion and excretion
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Eu=G-Rab+Sec ; urinary excretion = amount os S filtered through glomerulus - amount of S reabsorbed + amount of S secreted
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hat is the estimated renal plasma flow
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635 ml/min
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***What substance had 0 venous output
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paraAminohippurate PAH is used to derive RPF because equation RPF=Cpah=Eu/Ppah
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Does reabsorption or secretin dictate more of what is seen in urine
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reabsorption has a greater impact
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What is tubular reabsorption |
movement of components in filtrate back into blood of peritubular capillaries/vasa recta; this is carried out by epithelial cells |
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What is the flow path of the filtrate
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proximal tubule, descending LOH, asccending LOH, distal tubule, collecting tubule, collecting duct and pelvis
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What is the most important factor in regulating extracellular volume and osmolality
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reabsorption/excretion of Na+ which results in passive reabsorption of Cl- and H2O
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What constitutes a sizable fraction of filtrate
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Waste products like urea that are not easily reabsorbed
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What makes up a small fraction of the filtrate
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useful components that get reabsorbed easily like water electrolytes and glucoes
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What materials are readily reabsorbed
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H2O glucose Na+ K+ Ca+2 Cl- HCO3- HPO4
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how does active transport of Na+ then cause passive transport of both Cl- and H2O
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Na+ moving makes a charge difference cause Cl- to move over to balance. Then there is a higher concentration of H2O in tubules than in the capillaries so H2O moves due to osmosis
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How does tubular reabsorption work for Na+ |
crosses luminar membrane through cell cytoplasm and crosses basolateral membrane into interstitial fluid through capillary membranes and into plasma |
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What are the two types of tubular reabsorptoin
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trancellular transport and paracellular transport
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Describe transcellular transport
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create a pump leak system with active transport in one side and passive transport on the other to get cellular entry, trancellular diffusion and cellular exit
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describe paracellular transport
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paracellular shunt had passive movement through tight junctions and then through intercellular space and pass through basement membrane
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what are the two types of passive reabsorption
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simple diffusion and facilitated diffusion
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How does passive reabsorption work
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moves with the concentration gradient; a difference in concentration or electrical gradient causes movement and there is no energy required
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what do particles moved by facilitated diffusion flow through |
facilitated diffusion occurs by way of carrier proteins |
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Describe process for finding difference in electrical gradient
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delta E= Em -Eq = actual membrane voltage - nernst potential for ion; if delta E is 0 there is no transport but if delta E is negative, cation positive particles will be directed into the cell
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How does active transport work
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particles move against concentration/electrical gradient requiring energy to move
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What is tubular transport max
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max amount of substance that can be reabsorbed under any condition; Na+ has no tubular max
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Describe diabetes affecting Tm (tubular max)
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glucose levels rise in plasma due to pancreas problems producing insulin this causes not all glucose is reabsorbed like normal because concentration is so already therefore glucose is lost in urine
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Is there a tubular max for Na+
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no
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When there is a small increase in ingested concentration what happens to concentration excreted
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larger increase in concentration excreted than the amount ingested
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Does the kidney directly regulate plasma concentration of substances by reabsorption
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NO because absorption rate is subject to physiological control from hormones like aldosterone and ADH
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What is tubular secretion
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transport substances from peritubular capillaries to tubular lumen
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Is tubular secretion active or passive transport
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both
what are the two main functions of secretion |
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what are the two main functions of secretion
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removal of certain materials and partial control of pH
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what are secreted substances
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K+ H+ ammonia creatine penicillin
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where does most reabsorption and secretion take place
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proximal tubules 65% occurs here
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why do most reabsorption and secretion occur in proximal tubules
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Proximal tubules have a ton of mitochondria for active transport, luminal and basolateral membranes expand for transport, tight junctions aren't really that tight and brush boarder increases surface area for transport
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Where does drug detox occur
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Proximal tubules because active secretion of organic acids
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Does reabsorption/secretion occur in descending LOH
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really only reabsorption of H2O occurs because very few mitochondria and nu brush border therefore not much transport
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Does reabsorption/secretion occur in ascending LOH
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Only reabsorption; Brush border reestablished, but very tight tight junctions and nearly impermeable to H2O but strong transport of Na+ Cl- and K+
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How is the distal tubule related to ascending limb of LOH
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first half of distal tubule functions the same as the ascending limb
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How does the distal tubule differ?
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epithelial cells impermeable to urea and reabsorption of Na+ controlled by hormone aldosterone; increase in aldosterone yields increase in Na+ reabsorption and therefore causing K+ to be secreted due to the Na+ K+ pump;Reabsorption of H2Ois controlled by antidiuretic hormone ADH; increase in ADH yields increase in H2O reabsorption
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Where are aldosterone and ADH released
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Both are controlled by central nervous system but Aldosterone is released from adrenal cortex near kidney and ADH is released from posterior pituitary gland in the hypothalamus
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How does reabsorption/secretion work in the collecting duct |
less influence of aldosterone but ADH still regulates H2O reabsorption and slight increase in urea reabsorption and H+ is secreted against high concentration to balance pH |
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What has the highest concentration in the collecting duct |
urea |
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What reabsorption task takes to most energy and why |
Na+ reabsorption because it freely filters through glomerulus and there is no secretion and no reabsorption limit. 99.6% is reabsorbed but must go against electrochemical gradient so it requires a lot of energy |
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Why does the concentration of K+ increase at start of distal tubule |
because Na+ is reabsorbed through Na+ K+ pump: Na+ is reabsorbed and K+ is secreted |
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What are three ways Na+ enters epithelial cells along different spots of the nephron
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Na+ H+ exchange, cotransport of other solutes & Na+ selective channels
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Where do these mechanisms occur on the nephron
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Na+H+ exchange and cotransport of glucose and amino acid in PT; Na+K+ 2Cl- cotransport in thick ascending limb;Na selective channels in CT
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Is Cl- and H2O reabsorption passive
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Yes because depends on active transport of Na+
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How does Na+ come in during cotransport
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through carrier proteins
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How does aldosterone influence Na+reabsorption?
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In late distal tubule and CT, Na+ reabsorption rate controlled by blood concentration of aldosterone; an increase in aldosterone concentration will yield and increase in NA+ reabsorption
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What is aldosterone directly responsible fore creating
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carrier proteins which will transport Na+
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What happens in Addisons disease
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there is too little Aldosterone and there is an increase inuring output
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Does the auditory system have both afferent and efferent pathways |
yes |
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What are the three main structure of the ear
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External, middle, and inner ear
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What substructures are in the external ear
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Pinna and external auditory canal
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What is the purpose of the Pinna
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Accentuates some frequencies depending on sound wave angle of impact
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What is the function of the external auditory canal
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protects against damage
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What are the two substructures in the middle ear
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Tympanic membrane (ear drum) and ossicles: malleus, stapes, and icus which are all soft bones
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Describe how a wave is absorbed by the ear
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Pressure wave vibrates tympanic membrane which gets transmitted through ossicles but only 3-4% is transmitted and amplifies while the rest is deflected
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How is the energy amplified
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Leverage of the malleus in 1.3*incus and eardrum is 17*bigger than stapes footplate = 22fold increase
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what are the substructures of the inner ear
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Cochlea Oval window and round window
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What are the three canals of the cochlea
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scala vestibuli, tympani &media
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Where is the organ of Corti located and what does it use to transduce auditory signals |
located in Scala Media in cochlea in inner ear. It has inner/outer hair cells, basilar membrane & tectorial membrane which transduce the signals |
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What connects the scala vestibuli with the scala tympani
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Perilymph which freely floats between them
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What is the scala media filled with
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endolymph with high concentration of K+
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how does mechanical system become an electrical signal?
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Pressure gradient in fluid causes conversion into electrical signal that flows through hair cells yielding a graded potential and then an action potential in the ganglion cell
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What is the difference between inner and outer hair cells
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Single row of 3500 inner cells with divergence therefore they make up 92% of afferent nerve connections. While outer hair cells have 3 rows of 20,000 and go through convergence therefore only making up 8% of afferent nerve fibers
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Describe inner hair cell divergence
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1 inner hair cell connects to 10 spinal ganglion cells therefore 10 nerve fibers and therefore 35000 total connections
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Describe outer hair cell convergence
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6 outer hair cells connect to a single ganglion cell and therefore 1 nerve fiber yielding a total of 3000 nerve fibers
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What is the hypothesis behind the purpose of outer hair cells
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Amplification of inner hair cells by way of a filament that can contract and withdraw from tectorial membrane
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What are the 3 characteristics of Sound
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Pitch which is the frequency of vibration, Volume which is the amplitude of basilar membrane oscillation and tone which is the harmonic or overtone or brains interpretations of hair cell pattern
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Describe the mechanism of hearing
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Vibrating air enter the auditory canal, vibrate tympanic membrane, gets amplified by ossicles, and moves oval window which moves perilymph and bulges round window. Fluid movement oscillates basilar membrane, bending hair cells against tectorial membrane, which activated stretch sensitive ion channels. K+ ions from endolymph flow into hair cell through ion channels and create a gradient potential as they go from the apex to the base and then they depolarize causing Ca+2 to enter from nucleus of hair cell.Ca+2 causes the release of neurotransmitters like glutamate which travels across synapse, excites ganglion cells which generates oscillating AP that gets transmitted to auditory complex in temporal lobe.
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What are the two theories behind hearing
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Resonance theory and traveling wave theory
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Describe Resonance theory
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continuous spectrum of resonance on basilar membrane with high frequency resonance on stiff part at base and low frequency resonance at flexible part of apex
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Describe traveling wave theory
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acoustic vibrations hitting oval window elicit traveling wave within cochlear fluid causing basilar membrane and therefore mechanical energy transferred to hair cells. Peak amplitude determines where sound is heard on basilar membrane
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Is K+ 100% filterable at the glomerulus
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Yes
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Where is K+ active and passive
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active in CT but passive in PT
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Describe secretion process of K+
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Active Na+K+ pump in basolateral membrane increases concentration in epithelial cells; K+ partially diffuses across basolateral membrane into interstitial fluid and majority diffuses across membrane into tubular fluid
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What are the two main factors controlling K+ ion concentration
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1. Direct effect of increasing K+ in the ECF causes an increase in tubular secretion.
2. Aldosterone increases K+ secretion |
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What is urine dilution
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excretion of excessive water in urine due to low osmolality
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What is urine concentration
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excretion of excessive solute due to high osmolality
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What occurs with urinary dilution with an absence of ADH
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DT and CD become impermeable to water and water remains in tubules so urine is diluted due to the water being excreted
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What happens to osmolality from LOH to CD
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drops from 500-700 to 65-70 therefore it is diluted
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What are th two steps in forming concentrated urine
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hyperosmolality of medullary interstitial fluid(causes H2O to move out of tubules)
2. H2O reabsorption due to ADH |
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Describe counter-current exchange mechanism
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the set up of LOH and vasa recta where fluid is flowing in opposite directions but through exchanges, the concentration stays the same across various levels of the tubules
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How is hyperosmolality achieved
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solutes are moved into interstitial fluid by:
1. active Na+ transport from ascending limb 2. active Na+ transport and Cl- from CD 3. Passive diffusion of urea from CD 4. passive transport of Na+ and Cl- from thin LOH |
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Describe how ADh controls urine concentration
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posterior pituitary gland released ADH yields an increase in H2O reabsorption in DT, CT & CD
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Describe hypothesis behind ADH functions
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ADH activates adenyl cycles in basolateral membrane and that causes cyclic AP to form and diffuse into luminary membrane which causes an increase in permeability to H2O
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What does osmolality depend on in DT, CT, and CD
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ADh
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Describe the pathway of osmolality
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steady in PT, rapid rise in descending LOH and fall in ascend
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what are the 3 muscles in the bladder
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Detrusor, internal urethral sphincter and external urethral sphincter
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What is the Detrusor muscle
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smooth muscle forming the bladder wall
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What is the internal vs external sphincter
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internal in smooth while external is circular layered skeletal
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What is Micturition
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elimination of urine from bladder; spinal reflex influenced by higher brain centers
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Describe the process of urination
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Filled bladder brings stretch receptors to cause a DRG AP causing the innervation of the detrusor muscle and the inhibition of the innervated external sphincter muscle which causes relaxing and urination
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What occurs in voluntary delay of micturition
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descending paths from CNS inhibit detrusor muscles while stimulating external sphincter
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What is urinary incontinence
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lack of urinary control due to unconsciousness muscle injury, spinal innervation, emotional stress, incomplete development
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what do kidneys regulate to maintain homeostasis
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blood volume, ECF volume, osmolality, electrolyte concentration, and access/base balance
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What is the kidney feedback mechanism for blood volume control
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increase in BV yields increase in Cardiac output yields increase in arterial pressure yields increase in urinary output and a return of BV
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How does ADh control Blood Volume
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ADH enhances H2O reabsorption in DT, CT< and CD... if baroreceptors inhibit hypothalumus ADH decreases and H2O reabsorption decrease and urinary output increases
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How does aldosterone control blood volume
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causes excessive salt reabsorption in DT and CT and therefore the reabsorption of H2O
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what is the most abundant extracellular cation
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Na+
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What is the most important mechanism for ECF and osmolality regulation
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control of renal excretion of Na+ and H2O
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what are the two factors controlling concentrations of Na+ in the ECF
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the osmoreceptor/ ADH system and thirst mechanism
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describe the osmoreceptor
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osmoreceptors get excited due to osmolality changes and cause pituitary gland to release ADH
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Describe the thirst mechanism
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thirst is conscious desire for water and center location lateral pre optic area of hypothalamus; nerves excited yield thirst sensation
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What is the most abundant in the intracellular fluid
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K+
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What are the roles of K+
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AP production, neural skeletal and cardiac muscle function, maintain cell volume and pH
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What factors control the ion concentration of K+
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direct effect of increasing K+ and the effects of aldosterone
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What does an increase in the concentration of K+ do
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increase the rate of K+ secretion in the DT and CT
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what does aldosterone do to K+ concentrations
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secondarily increases secretion due to Na+ reabsorption; However ion concentrations of K+ in Ecf controls release of aldosterone by way of a negative feedback loop. an increase in aldosterone due to an increase in K+ yields and increase in the amount of K+ secreted which results in a decrease in the ion concentration of K+ in ECF which then causes a decrease in the amount of aldosterone released
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What is Ca+2 important for
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blood coagulation, neurotransmitter release, nerve muscle excitability and muscle tone
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Is Ca+2 completely filterable at glomerulus
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Yes
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What 2 hormones regulate the ion concentrations of Ca+2
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Parathyroid hormone and calcitonin
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Describe the role of parathyroid hormone PTH
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an increase in the reabsorption of Ca+2 in ascending LOH and DT
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What does Calcitonin do
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produce parafollicular cells of the thyroid gland
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What is primary aldosteronis
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Hypokalemia:tumor in the adrenal gland causes an excessive amount of aldosterone secretion which causes an extreme drop in K+ ion concentration and then there is an AP production and transmission failure
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What is addisons disease
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Hyperkalemia: no aldosterone due to destroyed adrenal glands which yields a 2fold increase in K+ concentrations in the ECF and then there is abnormal cardiac function and even death if cardiac arrest occurs
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