Card Set Information

2015-02-19 17:27:07

Chapter 20 Part 3 Urinary
Show Answers:

  1. What is the formula for net urine output?
    (Glomular Filtration + Tubular Secretion) - Tubular Reabsorption
  2. What is the effect of vasoconstriction of the afferent arteriole on GHP and GFR?
    Vasoconstriction would decrease GHP, thus decrease GFR
  3. Describe the relationship between net filtration pressure and glomerular filtration rate.
    The most important factor is GHP; if the afferent arteriole constricts, NFP decreases and GFR decreases; if the efferent arteriole constricts, NFP increases and GFR decreases
  4. The junction of the afferent arteriole and DCT, secretes renin when glomerular blood pressure falls.
    Juxtaglomerular Complex
  5. Supporting cells that lie between adjacent glomerular capillaries, they control capillary diameter and rate of blood flow.
    Mesangial Cells
  6. Occurs when there is too much glucose in the urine to be reabsorbed in the PCT, the result is that glucose remains in the urine.
    Renal Plasma Threshold
  7. What are the 3 triggers of renin release by the juxtaglomerular apparatus?
    1) Low BP (sensed by JG cells) 2) Sympathetic Nerves 3) Low Na (sensed by macula densa)
  8. Describe the 3 types of transport mechanisms found in the DCT.
    1) Na/K Exchange 2) Na/H Exchange 3) Secretion of toxins and drugs
  9. What would be the result of increased amounts of aldosterone?
    Since aldosterone increases reabsorption of Na, it would cause a decrease in plasma levels of K and H
  10. List the 2 intrinsic methods of controlling glomerular filtration rate.
    1) Myogenic Mechanism 2) Tubuloglomerular Feedback
  11. Describe how the intrinsic method of myogenic mechanism regulates GFR.
    When MAP goes up, it causes the afferent arterial to vasoconstrict to lower MAP, and vice versa
  12. Describe how the intrinsic method of tubuloglomerular feedback regulates GFR.
    When MAP goes up, the macula densa senses increased Na and releases prostaglandins, which delivers paracrine to stimulate JG cells, which cause the afferent arteriole to vasoconstrict
  13. What ranges of blood pressure will the intrinsic methods be able to maintain a relatively constant GFR?
    If MAP is between 70-170 mm Hg
  14. List the 2 extrinsic methods of controlling glomerular filtration rate.
    1) SNS Control 2) Renin Angiotensin Aldosterone System
  15. Describe how the extrinsic method of the SNS regulates GFR.
    The SNS stimulates the afferent arterial, which causes it to vasoconstrict, in order to regulate GFR
  16. Describe how the extrinsic method of the renin angiotensin aldosterone system regulates GFR.
    1) ADH releases vasopressin, which vasoconstricts the afferent arterial, decreasing GFR 2) Renin Angiotensin, which releases angiotensin II, causing vasoconstriction, decreasing GFR 3) Atrial Naturetic Peptide, which causes vasodilation, increasing GFR
  17. During tubular reabsorption, this is when the plasma concentration of a substance increases to a critical level in which more substances are in the filtrate than the active transport mechanisms can handle.
    Renal Plasma Threshold
  18. Glucose is excreted in urine when its concentration exceeds the renal plasma threshold, indicating what condition?
  19. Any increase in urine volume is known as what?
  20. When non-reabsorbed glucose in the tubular fluid increases the osmotic concentration of the tubular fluid.
    Osmotic Diuresis
  21. Describe which conditions exist which supports the passive reabsorption of water from the proximal convoluted tubule into the peritubular capillary.
    Water is reabsorbed by osmosis passively because Na is reabsorbed actively in the PCT, and wherever Na goes, water follows
  22. What is the law of Na and water in tubular reabsorption?
    Wherever Na goes, water follows (so if Na reabsorption increases, water reabsorption increases)
  23. What does the countercurrent mechanism of the vasa recta do?
    Ensures that the medulla is hypertonic by helping to maintain the NaCl concentration in the medulla
  24. What are the 2 main results of the loop of henle?
    1) Recovers water 2) Makes the medulla hypertonic
  25. Why is it important that the hypertonic solution in the renal interstitium be maintained?
    Because even the slightest change in tubular reabsorption of Na and water will result in large changes in urinary excretion of Na and water
  26. Chemicals that promote urine production are known as what?
  27. Give 3 examples of substances that are secreted into the renal tubules.
    1) Drugs 2) Histamine 3) Ammonia
  28. What is the main purpose of the renin angiotensin aldosterone system?
    To reduce fluid loss and increase blood pressure
  29. By what mechanisms does aldosterone reduce fluid loss and increase blood pressure?
    It recovers Na by triggering Na/K exchange to pump Na into the blood supply and K out of blood supply. This causes an excess in fluids in the blood supply (Na and water) and increases blood pressure (as well as GFR)
  30. By what mechanisms does ADH reduce fluid loss and increase blood pressure?
    It recovers water by creating aqua porins in the collecting duct, causing an increase in fluids in the blood supply, and increasing blood pressure
  31. What is the major hormone that regulates Na levels?
  32. What are the 5 triggers of aldosterone release?
    1) Hyperkalemia 2) Hyponatremia 3) Hypotension 4) Reduced Total Blood Volume 5) Renin-Angiotensin System
  33. What are the effects of aldosterone?
    1) Increases development of Na/K gates in DCT/CD (principal cells) 2) Increase Na retention/ K release; (and as Na is retained, water follows)
  34. Na is never _____, K is never _____.
    Secreted; Reabsorbed
  35. What are the primary and secondary triggers for K release?
    Primary: Hyperkalemia; Secondary: Aldosterone from adrenal cortex in response to increased K in ECF
  36. How is K secreted?
    1) Thru active secretion via cortical collecting duct (principal cells) 2) H/K exchange (intercalated cells)
  37. What 2 main things will the kidney do to compensate for alkalosis?
    1) Decrease H+ secretion into urine 2) Decrease HCO3 secretion into blood
  38. What 2 main things will the kidney do to compensate for acidosis?
    1) Increase H+ secretion into urine 2) Increase HCO3 secretion into blood
  39. What are the normal values for Blood pH, and HCO3?
    Blood pH: 7.35-7.45; HCO3: 22-26MEq/L ~ use 24 as a working value
  40. An alkaline condition of arterial blood >7.45
    Alkalemia (alkalosis is the process of causing alkalemia)
  41. An acid condition of arterial blood <7.35
    Acidemia (acidosis is the process of causing acidemia)
  42. What triggers the release of atrial naturetic peptide, and what is the effect?
    Triggered by stretching of the atria due to increased blood volume, it’s an extrinsic method under hormonal control of regulation of GFR, its effects is vasodilation of the afferent arteriole, increasing BP
  43. The opening of the urethra and the 2 openings of the ureters.
  44. The collection of smooth muscle fibers in the wall of the bladder.
    Detruser Muscle
  45. This is located in the neck of the bladder and functions to prevent the bladder from emptying until the pressure within increases to a certain level.
    Internal Urethral Bladder
  46. This is located as part of the urogenital diaphragm and functions to voluntarily control urination.
    External Urethral Bladder
  47. The urination reflex, started by stretch receptors in the bladder, and ending with relaxation of the external urethral bladder, expelling urine.