1. PowerPoint Lecture Outlines to accompany
Hole’s Human
Anatomy and Physiology
Tenth Edition
Shier w Butler w Lewis
Chapter 20
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Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. Chapter 20 Urinary System
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3. Location of Kidneys
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4. Kidneys
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5. Renal Blood Vessels
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6. Renal Blood Vessels
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7. Glomerular Capsule
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8. Nephron and Associated Blood Vessels
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9. Renal Cortex and Renal Medulla
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10. Juxtaglomerular Apparatus
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11. Types of Nephrons cortical nephrons 80% of nephrons
juxtamedullary nephrons
regulate water balance
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12. Blood Supply of Nephron
The capillary loop of the vasa recta is closely associated with the nephron loop of the juxtamedullary nephron
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13. Summary of Blood Flow Through Kidney and Nephron
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14. Urine Formation Glomerular Filtration
substances move from blood to glomerular capsule
Tubular Reabsorption
substances move from renal tubules into blood of peritubular capillaries
glucose, water, urea, proteins, creatine
amino, lactic, citric, and uric acids
phosphate, sulfate, calcium, potassium, and sodium ions
Tubular Secretion
substances move from blood of peritubular capillaries into renal tubules
drugs and ions
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15. Glomerular Filtration
Glomerular filtrate passes through the fenestrae of the capillary endothelium
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16. Glomerular Filtrate and Urine Composition
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17. Glomerular Filtration Rate
Net Filtration Pressure = force favoring filtration – forces opposing filtration
(glomerular capillary ( capsular hydrostatic pressure
hydrostatic pressure) and glomerular capillary
osmotic pressure )
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18. Amounts of Glomerular Filtrate and Urine
average amounts over a 24 hour period
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19. Control of Filtration Rate
Increased sympathetic impulses decrease GFR by causing afferent arterioles to constrict
Renin-angiotensin system (shown)
Autoregulation
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20. Tubular Reabsorption
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21. Tubular Reabsorption of Water and Ions
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22. Sodium and Water Filtration, Reabsorption, and Excretion
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23. Tubular Secretion
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24. Secretion of Ions
In distal convoluted tubules, potassium ions or hydrogen ions may be passively secreted in response to active reabsorption of sodium ions
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25. Countercurrent Mechanism
helps maintain the NaCl concentration gradient in the medullary interstitial fluid
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26. Countercurrent Mechanism of Vasa Recta
fluid in ascending limb becomes hypotonic as solute is reabsorbed
fluid in descending limb becomes hypertonic as it loses water by osmosis
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27. Effect of ADH on Renal Tubules
without ADH, DCT and collecting duct are impermeable to water
with ADH, DCT and collecting duct become permeable to water
with ADH, water is reabsorbed by osmosis into hypertonic medullary interstitial fluid
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28. Urea and Uric Acid Excretion
product of amino acid catabolism
plasma concentration reflects the amount or protein in diet
enters renal tubules through glomerular filtration
50% reabsorbed
rest is excreted
Uric Acid
product of nucleic acid metabolism
enters renal tubules through glomerular filtration
100% reabsorbed
10% secreted and excreted
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29. Renal Clearance
the rate at which a chemical is removed from the plasma
tests of renal clearance
inulin clearance test
creatinine clearance test
paraminohipparic acid test
tests of renal clearance used to calculate glomerular filtration rate
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30. Elimination of Urine nephrons collecting ducts renal papillae
minor and major calyces
renal pelvis
ureters
urinary bladder
urethra
outside world
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31. Ureters
25 cm long
extend downward posterior to the parietal peritoneum
parallel to vertebral column
in pelvic cavity, join urinary bladder
wall of ureter
mucous coat
muscular coat
fibrous coat
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32. Location of Male and Female Urinary Bladders
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33. Urinary Bladder
Longitudinal section and posterior view of male urinary bladder
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34. Cross Section of Urethra
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35. Male and Female Urethras
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36. Micturition bladder distends and stretch receptors stimulated
micturition center activated in sacral portion of spinal cord
parasympathetic nerve impulses cause detrusor muscle to contract
need to urinate is sensed
voluntary contraction of external urethral sphincter prevents urination
when decision is made to urinate, external urethral sphincter relaxes, detrusor muscle contracts, and urine is expelled
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37. Life-Span Changes kidneys appear scarred and grainy kidney cells die
by age 80, kidneys have lost a third of their mass
kidney shrinkage due to loss of glomeruli
proteinuria may develop
renal tubules thicken
harder for kidneys to clear certain substances
bladder, ureters, and urethra lose elasticity
bladder holds less urine
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38. Clinical Application Glomerulonephritis inflammation of glomeruli
may be acute or chronic
acute glomerulonephritis usually occurs as an immune reaction to a Streptococcus infection
antigen-antibody complexes deposited in glomeruli and cause inflammation
most patients recover from acute glomerulonephritis
chronic glomerulonephritis is a progressive disease and often involves diseases other than that caused by Streptococcus
renal failure may result from chronic glomerulonephritis
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