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251 Cards in this Set
- Front
- Back
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What are the functions of the kidneys? (8)
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1. regulation of blood ionic composition
2.regulating blood pH 3.regulating blood volume 4.regulating blood pressure 5.maintaining blood osmolarity 6.producing hormones 7.regulating blood glucose 8. excreting waste and foreign substances |
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what ions do the kidneys regulate?
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Na+, K+,Ca2+, Cl-, Phosphate ions
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Give two examples how the kidneys regulate blood pH.
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1. excretes variable amounts of H+
2. conserves bicarbonate ions |
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How do the kidneys regulate blood volume?
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by either conserving or eliminating water
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what enzymes are important for regulating blood pressure?
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(renin-anglotesin-aldosterone)
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what is the osmolarity of the blood?
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290-300 milliosmoles/per liter
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How can kidneys regulate blood osmolarity?
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seperates water from the ions
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What hormones do the kidneys produce?
and what do they do? |
calcitriol- active form of vit. D, regulates Ca2+
erythropoietin-stimulates RBC production |
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How do the kidneys regulate blood glucose?
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synthesis of new glucose molecules by using amino acid glutamine
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During the excretion of wastes the following turn into...
1. amino acids----> 2.hemoglobin-----> 3. creatine phosphate----> 4. nucleic acids-----> |
1. ammonia and urea
2.bilirubin 3. creatinine 4.uric acid |
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The urinary system is composed of...
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two pairs of kidneys, two ureters, urinary bladder, urethra
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The nephron filters how many liters of fluid per day?
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180 L
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In a female, the urethra is where?
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-posterior to pubic symphesis
-4 cm long -opens to outside world between clitoris and outside opening |
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In the male the urethra is where and how long?
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-passes through the prostate gland and the penis
-15-20 cm long -does double the work than a females because it is part of the reproductive tract |
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What is the mucosa and its function in the female urethra?
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-mucous membrane
-epithelial cells -lamina propria=basement membrane -helps isolate from effects of urine (acidic) |
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What are the three parts of the female urethra?
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1. transitional epithelium-can expand when urine is full
2.stratified columnar or psuedostratified columnar 3.non-keratinized stratified squamous |
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What is the muscularis of the female urethra?
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-layer of smooth muscle
-circular fibers -continues from urinary bladder |
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What are the three parts of the male urethra?
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1. starts with transitional ep. becomes stratified columnar or psuedostratified columnar
2. membranous urethra=stratified columnar or psuedostratifed columnar 3.spongy urethra= begins with stratified columnar or pseudostratified columnar but ends with non-keratinized stratified squamous ep. |
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What function does the mucous membrane serve in the male urethra?
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protection-barrier that protects the cells from osmolarity and acidity of the urine
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what is the urinary bladder
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Hollow muscular organ, found inside the pelvic cavity
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Where is the urinary bladder found in female?
...in males? |
females=anterior to vagina and inferior to uterus
males=anterior to rectum |
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What are the four parts of the urinary bladder?
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1.Trigone
2.Mucosa 3. Muscularis 4.Two sphincter muscles |
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How is the trigone formed in the urinary bladder?
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formed by:
1. two uretal openings 2.internal urethra orifice |
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What is the mucosa of the urinary bladder made of?
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-Trasitional ep.
-rugae -folded |
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What is the muscularis of the urinary bladder made of?
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-smooth muscle
-detrusor muscle |
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What are the three layers of the muscularis in the urinary bladder?
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1.inner longitudinal
2.middle circular 3.outer longitudinal |
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What are the two sphincter muscles of the urinary bladder?
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1.internal urethra sphincter
-smooth muscle -extension of wall of bladder 2.external urethra sphincter -skeletal muscle |
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How much urine can the bladder hold?
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700-800 mL of urine
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when will the stretch receptors be activated in the bladder?
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at 200-400 mL of urine
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Which organs are retroperitoneal? and what does that mean?
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The ureters
-behind the peritoneum |
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In which gender does the urinary system and the reproductive system over lap?
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Males
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which gender has the smaller bladder?
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Females
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What does the term micturition mean?
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The urination process
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Explain the micturition reflex and the three causes...
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1. Stretch receptors will transmit a signal to the spinal cord (between S2 and S3)
2.This triggers a reflex and the parasympathetic impulses fo to the urinary bladder which causes: a. constriction of detrusor muscle b.relaxation of internal urethra sphincter c.stop in stimulation of the external urethra sphinctor=urination |
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The ureters transport urine from the...
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kidneys to the bladder
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How long are the ureters?
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25-30 cm long
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Diamater of wall increases or decreases as the ureters descend?
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increases
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As the bladder increases in size the angle of the ureters become more severe to do what?
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create a crimp in the uriter which creates a functional sphincter
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What are the three parts of the ureters?
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1. mucosa
2.submucosa 3.adventitia |
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What is the mucosa made of in the ureters?
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-mucous membrane
-lined with transitional ep. -supporting lamina propria |
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what are the three parts of the muscularis in the ureters?
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1.inner longitudinal layer
2.outer circular layer 3. outer longitudinal layer |
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What are the three ways urine is transported?
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1.peristaltic waves
2.gravity 3.hydrostatic pressure |
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Is there an anatomical sphincter at the union of the ureter and the bladder?
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no
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Explain the kidneys: Where they are, how long, wide, thick?
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-pressed up against posterior wall
-retroperitoneal -sit between T12 andL3 -protected by ribs 11 and 12(floating ribs) -10-12 cm long -5-71/2 cm wide -2.5 cm thick |
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What is the hilum of the kidney?
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entry for renal artery, renal vein, and ureter
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What are the three layers that surround the kidneys?
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1. outer layer-renal fascia
2.middle layer-adipose capsule 3. inner layer-renal capsule |
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What is the renal fascia in the kidney made of and what is its purpose?
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-dense irregular CT
-anchors the kidney in place |
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What is the adipose capsule in the kidney made of and what is its purpose?
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-adipose tissue
-prorection(shock absorber) -anchors kidneys in place |
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What is the renal capsule in the kidney made of and what is its purpose?
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-smooth, transparent fibrous tissue
-barrier to pathogens |
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What two regions are the kidneys divided into?
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1. renal cortex
2.renal medula |
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What is the renal cortex of the kidneys?
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-outer redish area
-extensions between renal pyramids |
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Why is the renal cortex of the kidney reduced in color?
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Because of reduced concentrations of solutes in the tissue
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What is the renal medulla of the kidneys?
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-darker red area
-high concentration of solutes |
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How many renal pyramids lie in the renal medulla?
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8-18
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Aproximately how many nephrons are in the kidneys?
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100
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What kidney is more inferior in location and why?
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Right kidney because of the liver
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What are the extensions between the renal pyramids?
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Renal columns
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Explain the drainage of urine from the kidneys
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minor calyx--->major calyx----->renal pelvis---->ureter
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what drains one pyramid?...more than one pyramid?
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1. minor calyx
2. major calyx |
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Explain the flow of blood inside the kidney
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renal artery-->segmental arteries-->interlobar arteries
-->arcuate arterioles--> interlobular arteries--> afferent arterioles-->glomerulus--> efferent arteriole--> peritubular caps--> peritubular venules--> interlobular veins--> arcuate veins-->interlobar veins--> segmental veins--> renal veins |
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explain the renal artery
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-O2 unfiltered blood
-20-25% of resting cardiac output -1200 mL per min |
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explain the segmental arteries location and what it does
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-renal artery breaks up and divides into segmental arteries
-supplies blood to a segment of the kidney |
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where are the interlobar arteries of the kidney
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found between the pyraminds
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where are the arcuate arteries of the kidney
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arch over the base of renal pyramids
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where are the interlobular arteries
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-branches of arcuate arteries
-extend into the cortex |
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Where are the afferent arterioles and what is their function
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-enter the renal corpuscle
-larger arteriole than efferent= increases pressure -deliver blood to renal corpuscle |
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When does blood enter the nephron
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at the afferent arterioles
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what is the glomerulus
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-capillary bed inside the nephron
-blood enters from afferent arterioles |
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Where are the efferent arterioles and what do they do?
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-Extends off of glomerulus
-Smaller arteriole than afferent= decreases pressure |
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what is the second capillary bed?
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peritubular caps.
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What is the functional unit of the kidneys?
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Nephron
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What is a cortical nephron?
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-short loop of Henle
-80-85% of nephrons are this type |
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Renal veins are..
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-doxygenated filtered blood
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What is a juxtamedullary nephron?
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-long loop of Henle
-15-20% of all nephrons are this type |
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Vesa Recta occurs in what type of nephron?
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Juxtamedullary nephron
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Which nephron is next to the medulla and further from the renal capsule?
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Juxtamedullary nephron
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Which nephron is closer to the renal capsule?
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Cortical nephron
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What is the podocyte of the visceral layer of glomerulus made out of?
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Modified simple squamous ep.
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What are the mesangial cells made out of? and what do they do?
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-smooth muscle cells
-controls the size of the cap. bed by contracting |
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what structures make up the filtration membrane/endothelial capsular membrane?
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1.endothelial fenestrations of glomerulus
2. basement membrande of glomerulus 3.slit membrane between pedicals of the podocytes |
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what is the juxtaglomerular apparatus?
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1.part of ascending limb with macula densa cells
2.afferent arteriole with juxtaglomerular cells |
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what do the macula densa cells do?
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They read the concentration of solutes mainly HCL and send it to juxtaglomerular cells which respond by either increasing or decreasing blood flow into cap. beds
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endothelial fenestrations of glomerulus filters what?
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only filters cells (RBC,WBC, platelets)
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the basement membrane of the glomerulus filters what?
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filters large proteins
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the slit membrane between the pedicals of the podocytes filters what?
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filters medium sized proteins
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What is the proximinal convulted tubule made out of?
what is their function? |
simple cuboidal with brush border of microvilli that increases surface area for absorption
-reabsorption of filtered products |
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what is the descending limb of the loop of henle made out of?
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simple squamous ep.
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what is the ascending limb of the loop of henle made out of?
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simple cuboidal to low columnar
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What are the distal convoluted and collecting ducts made out of?
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simple cuboidal composed of principal and intercalated cells with microvilli
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what are the principal cells receptors for (2)?
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1.Antidiuretic Hormone (ADH)
2.Aldosterone |
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What is the function of the intercalated cells?
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play role in homeostasis of blood pH
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what are the three functions of the nephron?
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1.filtration
2.secretion 3.reabsorption |
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Filtration from blood plasma into what?
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into nephron
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Tubular reabsorption from fluid into what?
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into blood
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Tubular secretion from blood into what?
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into fluid
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what is the location of filtration?
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-renal corpuscle
-endocapsular membrane -greater volume of fluid |
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Why is the volume of fluid filtered by the renal corpuscle much larger than other capillaries of the body?(list 3 reasons)
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1.large surface area
2.filtration membrane is thin and porous 3.glomerular capillary pressure |
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how is large surface area regulated?
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can be regulated by mesangial cells (modified smooth muscle cells)
-can contract or relax to increase or decrease surface area |
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what causes a greater volume of filtration?
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large fenestrations
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why is there a higher than normal cap. (glomerular capillary)?
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because efferent arteriole is smaller in diameter than afferent arteriole which creates a larger pressure in glomerulus
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what is the pressure (at rest) in the glomerular capillary?
what does this allow you to do? |
55 mmHg compared to 30mmHg in a normal cap.
-allows you to force more material out |
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List 3 ways the Net Filtration Pressure can be influenced
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1.Glomerular blood hydrostatic pressure
2.Capsular hydrostatic pressure 3.blood colloid osmotic pressure |
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What does the capsular hydrostatic pressure responsible for?
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Forcing filtrate out of caps into capsular space (once it is filled forcing more fluid into it will create resistance)
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what is the normal capsular hydrostatic pressure
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15mmHg
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does the capsular hydrostatic pressure work against the filtration or with the filtration?
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against
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does the glomerular blood hydrostatic pressure work with filtration or against filtration?
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with filtration
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Does blood have more or less dissolved materials than filtrate?
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-more
-because more dissolved materials forces water to flow |
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what is the normal blood colloid osmotic pressure at rest?
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30mmHg
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does the blood colloid osmotic pressure work with filtration or against filtration?
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against filtration
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What three pressures are responsible for glomerular filtration?
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GBHP, CHP, BCOP
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Define net filtration pressure
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GBHP-CHP-BCOP
55mmHg-15mmHg-30mmHg |
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What is the typical NFP that produces a normal amount of blood plasma filtration?
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10mmHg
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What is the glomerular filtration rate?
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amt. of filtration formed in all renal corpuscles of both kidneys each min.
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What is the normal Glomerular Filtration Rate?
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125 mL per min. (being filtered and sent to the kidneys)
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What is the relationship between NFP and GFR?
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they are proportional
(a change in NFP will change GFR) |
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What is the equation for GFR?
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GFR=Kf times NFP
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what is the Kf?
-an increase in surface are will... |
measures permeability, surface area of membrane
-increase filtration -400 times higher than other caps. |
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Increase in NFP=
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loss of important solutes
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decrease in NFP=
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not enough filtered
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if BHP drops to 45 mmHg than what happens to NFP
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0 NFP- blood pressure filtration will stop
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What are the three mechanisms that regulate GFR ?
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1.renal auto regulation
2.neural regulation of GFR 3. hormonal regulation |
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Renal autoregulation consists of what two mechanisms?
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1.myogenic mechanism
2.tubuloglomerular feedback |
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Regulation of GFR in what two ways?
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1. adjusting blood flow into and out of glomerulus
2. altering glomerular cap. surface to increase or decrease surface area for filtration |
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what responds to normal every day changes in blood pressure?
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renal autoregulation
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what triggers the myogenic mechanism
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triggered by stretching of afferent arterioles which causes smooth muscle cells to contract
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during low blood pressure the myogenic mechanism does what
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increases afferent arteriole in diameter
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during high blood pressure the myogenic mechanism does what?
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decreases afferent arteriole in diameter
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Describe tubuloglomerular feedback (follows 7 stage path)
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1.an increase in GFR
2.cause an increase in delivery of Na+, Cl-, and H2O 3.which sends an input to the control center=juxtamedullary apparatus 4.which causes a decrease of the secretion of nitric oxide 5. which causes the afferent arteriole to constrict 6. which lowers blood flow into the renal corpusle 7. which decreases GFR |
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what type of cells meausre an increase in GFR?
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macula densa cells
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what is neural regulation of GFR and what is its funtion?
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1. sympathetic motor output to blood vessels
2. releases norepinephrine= vasoconstrictor |
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During Neural regulation of GFR what happens during moderately low stimulation?
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renal auto regulation dominates
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During Neural regulation of GFR what happens during moderate stimulation?
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little change in GFR
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During Neural regulation of GFR what happens during high stimulation?
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-vasoconstriction of afferent arteriole
-decrease urine output -more blood available to other parts of the body |
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what two hormones are important for hormonal regulation of GFR?
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1.angiotensin II
2. atrial natiurtetic peptide (ANP) |
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during hormonal regulation of GFR what does angiotensin II do?
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decreases GFR
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during hormonal regulation of GFR what does ANP do?
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-increases GFR
-an increase of GFR dumps extra fluid out of the body |
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which area of the tubule reabsorbs the most materials?
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proximinal convoluted tubule
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what are the reabsoorption routes of substances in the tubules?
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1. paracellular reabsorption
2. transcellular reabsorption |
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describe paracellular reabsorption
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-movement of materisals between cells into the interstitial fluid
-follows concentration gradiant |
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describe transcellular reabsorption
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movement of materials through a cell to the peritubular capillary
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during tubular reabsorption where is there a high concentration of Na+ and where is there a low concentration of Na+
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high=in the lumen
low=in the cell |
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Describe the transport mechanisms for renal solutes
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-secondary active transport
-Na+/K+ ATPase pumps -osmosis |
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explain secondary active transport for Na+ to enter the cell during tubular reabsorption
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-a high concentration of Na+ in the lumen and a low concentration of Na+ in the cells allow Na+ to travel down its concentration gradiant which allows Na+ to bring other things along with it (ie glucose)
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What type of transport mechanism is important during the reabsorption of Na+
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-Na+/K+ ATPase pumps the sodium from tuble of the cell cytosol through the basolateral membrane
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explain obligatory water reabsorption
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occurs when water is obligated (must) follow the solutes being reabsorbed (automatic)
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explain facultative water reabsorption, what hormone is used, and when does it occur?
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occurs in the collecting duct under the control of antidiuretic hormone
-occurs during dehydration |
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describe the process of reabsorption in the PCT
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Na+ is moving into the PCT while H+ is moving out of the PCT
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what is an antiporter?
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two or more molecules move in the opposite direction
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what is a symporter?
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two or more molecules move in the same direction
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What is left at the end of reabsorption in the PCT
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no organic materials left in solutes because they have been reabsorbed
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what is the osmolarity of the blood during the reabsorption in the PCT
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300 milliosmoles/Liter
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how much water is reabsorbed in the PCT
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65%
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what type of cells are in the PCT that help with absorption?
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simple cuboidal with microvilli
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Solutes of blood during reabsorption in the PCT is __________ as the filtrate leaving the PCT
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the same
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Which ions use diffusion to enter the peritubular capillary?
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Cl-, K+, Ca2+,Mg2+, and urea
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explain the reabsorption of bicarbonate ions outside the cell (in the lumen)
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HCO3- + H----->H2CO3(carbonic acid)-----> H20 + CO2 then CO2 is reabsorbed into the cell
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what happens to the reabsorption of bicarbonate ions inside the cell?
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CO2+ +H2O-----> H2CO3 (carbonic acid)-----> H+ + HCO3-
-we secrete the H+ and keep the HCO3- as a buffer |
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describe the process of reabsorption in the descending limb of the loop of henle
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-reabsorption of H2O (no solutes)
-concentration of filtrate increases -300 milliosmoles @ top of DL and 1200 milliosmoles @ end of DL |
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describe the process of reabsorption in the ascending limb of the loop of henle
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-reabsorption of only solutes
-becomes more and more dilute -leads to stratification(layerings) of concentration amounts -1200 milliosmoles at bottom of AL and 100 milliosmoles at top of AL |
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where is there a high concentration and a low concentration in the loop of henle?
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-high concentration=bottom of descending limp
-low concentration=top of ascending limb |
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true or false?
blood will always have a higher amount of solutes? |
True
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-describe the process of reabsorption in the distal convoluted tubule
-by the end of the DCT what happens to the water and solutes |
-removal of Na+ and Cl- continues
-Na+ and CL- then reabsorbed into the peritubular capillaries -by the end of the DCT, 95% of solutes and water have been reabsorbed and returned to the blood |
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describe the process of secretion in the collecting ducts
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-cells in the collecting ducts make the final adjustments
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what are the principal cells in the collecting duct responsible for?
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reabsorbing Na+ and secreting K+
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what are the intercalated cells in the collecting duct responsible for?
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reabsorbing K+ and bicarbonate ions and secreting H+
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what two hormones control the facultative H2O reabsorption?
what cells do they act on? |
1. aldosterone
2. antidiuretic hormone (ADH) -principal cells |
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how does the hormone aldosterone regulate absorption and secretion?
-what are they secreted by |
-secreted by the adrenal gland
-controls Na+ and H2O reabsorption -causes principal cells to synthesize more Na/K pumps and channels -stimulates secretion of K+ |
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high levels of aldosterone=
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low levels of Na+ in the filtrate
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low levels of aldosterone=
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more concentration of Na+ in urine which means more concentration of H2O in urine
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how does the hormone ADH regulate water reabsorption?
-where is it produced and released? |
-produced by the hypothalamus
-released by posterior pituitary gland -stimulates insertion of special water protein (aquaporin-2) channels which are designed for the movement of H2O |
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an increase in ADH means
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an increase in aquaporin-2 channels
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a decrease in ADH mean
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a decrease in aquaporin-2 channels
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which hormone has an indirect connection with H2O?
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aldosterone
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which hormone has a direct connection with H2O?
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ADH
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filtration after it passes through the collecting duct that cannot be changed and you do not have control over...
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urine
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what are the two different types of urine?
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1.concentrated urine
2.dilute urine |
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concentrated urine has an osmolarity...
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greater than blood
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dilute urine has an osmolarity...
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less than blood
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Explain dilute urine
-its concentration -reabsorption of what? |
-concentration less than 300 milliosmoles/ liter
-reabsorption of more solutes=more H20 in urine -low levels of ADH urine with concentrations of 65-70 milliosmoles |
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explain concentrated urine
-its concentration -2 important factors |
-concentration greater than 300 milliosmoles/liter no greater than 1200 milliosmoles/Liter
1. differences in the reabsorption of water and solutes in the loop of henle and the collecting duct 2.the countercurrent flow of fluid and blood |
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in the collecting duct, as ADH increases,
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water reabsorption increases
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in the collecting duct as ADH decreases,
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water reabsorption decreases
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describe how the collecting duct created concentrated urine (3 steps)
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1.the symporters in the hick ascending limb estabish an osmotic gradiant
2.the principal cells in the collecting duct reabsorb more H2O when ADH is present 3. urea recycling causes build up of urea in the renal medulla |
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How does the countercurrent mechanism play a role in the formation of concentrated urine?
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countercurrent mechanism= flow of blood is counter to the flow of fluid of filtrate
-this means that the water in the collecting duct is being reabsorbed by the blood and there is more solutes left in the urine=concentrated urine |
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name the six other body systems that play a part in waste management for the body
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1.buffers bind excess H+
2.blood transports waiste 3.Liver= site for metabolic recycling 4.lungs excrete CO2 and heat 5.sweat glands eliminate heat,water, salt and urea 6.the GI tract eliminates solid wastes, CO2, H2O, salt and heat |
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the female body is composed of what percentage solids and what percentage fluids
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45% solids
55% fluids |
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the male body is composed of what percentage solids and what percentage fuilds
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40% solids
60% fluids |
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what is the total body fulid broken up into?
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2/3 intracellular fluid
1/3 extracellular fluid |
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what is the extracellular fulid broken up into?
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80% interstitial fluid
20% plasma |
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how do the cells maintain homeostasis?
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by recieving and getting rid of nutriends and waste from and into the blood
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describe how the body maintains homeostasis though the bodys 48 liters of fluid
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6 liters of the 48 liters of fluid in the body is blood and 3 liters of that blood is plasma. If the 3 liters of fluid is controlled than the total 48 liters is controlled and the body maintains homeostasis
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what is the definition of electrolytes?
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-any substance that seperates into ions when dissolved in water
-they allow the conduction of electricity (ATP) |
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what is an example of an electrolyte?
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NaCL+H2O---->Na+ CL-
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how are electrolytes held together
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by ionic bonds
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what are nonelectrolytes?
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any substance that does not produce ions when dissolved in water
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how are nonelectrolytes held together?
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by covalent bonds
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what are some examples of nonelectrolytes?
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-glucose
-protein -lipids -urea |
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what are the four functions of electrolytes in the body
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1.control of osmosis
2.help maintain acid-base balance 3.carry electrical current 4.some are co-factors |
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what is more numerous nonelectrolytes or electrolytes?
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electrolytes
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how do electrolytes help maintain the acid-base balance?
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-help control pH via buffering systems
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what type of electrical currents are the electrolytes responsible for?
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-action potentials, certain secretions
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what is a co-factor?
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some electrolytes are the last bit needed to make an enzyme functional
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what has the highest osmolarity between: blood plasma, interstitial fluid, and intracellular fluid
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blood plasma (5443mmHg)
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what is the total osmotic pressure?
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electrolytes+nonelectrolytes
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what anions and ions are found outside the cell?
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Na+, Ca2+,Mg2+,Cl-, and HCO3-
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what anions and ions are found inside the cell?
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K+, phosphate(HPO4-), and proteins
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what is the most abundant extracellular cation in the body?
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Na+ = 90% of cations
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what cation accounts for 1/2 of the osmolarity of extracellular fluids?
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Na+
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what 4 hormones control the amount of Na+ in the body?
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1. angiotensin II
2. aldosterone 3.ADH 4.ANP |
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what 2 hormones act to increase Na+
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1.angiotensin II
2. aldosterone |
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what is the most abundant extracellular anion in the body?
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CL-
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what 3 hormones control CL-?
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1. angiotensin II
2.aldosterone 3.ANP |
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what is the most abundant intracellular cation in the body?
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K+
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what is one important function of K+?
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helps maintain fluid volume in cells
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what hormone is K+ controled by?
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aldosterone
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what is the most prevelant form of phosphate within the cells?
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HPO4 -2
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what is HPO4-2 (phosphate) controlled by?
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PTH and calcitonin
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what are the 3 different ways the body fluids move?
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1. vesicular transport
2.diffusion 3.bulk flow |
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what is bulk flow
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hydrostatic pressure overcomes osmotic pressure in arterial end and osmotic pressure overcomes hydrostatic pressure in venual end
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what type of movement are most materials moved by?
-with excpetion to what? |
-diffusion
-except for the brain and CNS |
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explain the exchange between interstitial fluid and intracellular fluid
-osmotic pressure -movement of water and solutes |
-osmotic pressure equal between both regions
-no net movement of water -movement of solutes through: 1. diffusion 2.active transport 3.vasicular transport |
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H+ have the greatest influence on what ions? how?
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-proteins
-they influence the stucture or shape |
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what is the normal pH of blood?
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7.35-7.45
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how do we produce such large amounts of H+
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via metabolism
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what are the three mechanisms that maintain H+ ion concentrations?
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1. buffer systems
2.exhalation of carbon dioxide 3. through the kidneys |
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how do buffer systems act to maintain H+ concentrations?
-how fast does it work? -what is it limited by |
-act quickly
-limited by concentration of buffer -removal of H+ from solution but not from the body |
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how does exhalation of carbon dioxide work to maintain H+ concentrations?
-how fast? |
-increase/decrease in the rate/depth of breathing influences the pH of the plasma
-acts within minutes -only eliminates carbon dioxide |
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how do the kidneys work to maintain H+ concentrations?
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-slowest system (hours/days)
-only way to eliminate acids other than carbonic acid from the body |
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what is a buffering system?
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composed of a weak acid and an anion of that weak acid
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what is a weak acid?
-example? |
an acid that does not completely dissassociate when put in a solution
-H2CO3------> some would dissassociate into H+ + CL- |
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what do buffer systems do?
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they prevent rapid and drastic change in pH
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if we increase pH then...
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then OH- increases
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if we decrease pH then...
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then H+ increases
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buffer system: when increasing OH- what happens?
A+H+A-+OH- -------> (buffer) |
2A-+HOH
-H will dissassociate and bind to OH- making H20 which stops the increase in pH |
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buffer system: when increasing H+ what happens?
A+H+A-+H+ ------> (buffer) |
2A-H
-Hydrogen ion will bind to anion which stops the decrease in pH |
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what are the 3 principal buffering systems of the body?
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1.protein buffer system
2.carbonic acid-bicarbonate buffer system 3.phosphate buffer system |
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what is the most abundant buffer system?
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protein buffer system
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where is the protein buffer system found?
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found inside cells and in the plasma
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what happens in the carboyxl group of the protein buffer system?
COOH turns into what? how? |
-releases H+ ions turns
COOH----->COO- + H+ |
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what happens in the amino group of the protein buffer system?
NH2 turns into what? how? |
-absorbs H+
NH2---->NH3 |
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how many side groups act as buffers in the protein buffer system?
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7 out of 20
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what is the weak acid, anion, and buffer in the carbonic acid buffering system?
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H2CO3=weak acid
H+= anion H2CO3+ HCO3-= buffer |
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if we increase H+ in the carbonic acid buffering system what happens
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H2CO3+HCO3- +H+------> 2H2CO3
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if we increase OH- in the carbonic acid buffering system what happens
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H2CO3+HCO3- + OH- ------>
2HCO3- + HOH |
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what happens in the lungs regarding pH?
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-pH of blood can be adjusted by breathing patterns usually within 1-3 mins.
-if you increase your ventilation by 2X the normal rate you can increase pH by 0.23 -makes pH no longer in normal range |
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How do kindneys control H+
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metabolic reactions produce fixed acids which changes of pH causes secretion of H+ out of the kidneys
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what is a fixed acid?
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nonvolatile acid
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how do you remove volatile acides?
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through the lungs (CO2) exhalation
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what are volatile acids?
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can be converted into gas
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Can the lungs protect against respiratory induced pH changes?
why? |
no because were breathing CO2 out
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what buffering system is important for intracellular control of pH changes?
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phosphate buffer system
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