Chapter 27

64. If the hydrogen ion concentration in the blood increases, bicarbonate ions act as buffers by A) removing excess hydrogen ions from the plasma. B) releasing hydrogen ions into the plasma. C) dissociating into H+ and CO3-. D) combining with chloride ions. E) combining with hemoglobin.

a

7. The predominant intracellular cation is A) potassium. B) sodium. C) calcium. D) magnesium. E) chloride.

a

42. In hypocalcemia, A) depolarization is prevented. B) PTH production is reduced. C) blood calcium levels are increased. D) neuromuscular excitability increases. E) neuromuscular excitability decreases.

d

51. Calcitonin A) promotes the absorption of calcium from the gastrointestinal tract. B) promotes osteoclast activity in the bones. C) reduces calcium excretion by the kidneys. D) reduces extracellular calcium ion levels. E) increases blood calcium levels.

d

56. Which of the following is an example of water conservation by the body? A) diarrhea B) perspiration C) decreased water intake D) decreased urine volume E) increased urine volume

d

72. Which of the following can play a role in buffering the pH of urine? A) ammonia B) bicarbonate ions C) phosphate ions D) A and B only E) A, B, C

e

65. Which of the following is not a buffer system of the body? A) bicarbonate buffer system B) phosphate buffer system C) protein buffer system D) NaCl buffer system E) hemoglobin buffer

d

68. An increase in blood CO2 levels is followed by a(n) ____ in H+ ions and a(n) ____ in blood pH. A) decrease, decrease B) decrease, increase C) increase, increase D) increase, decrease E) increase, no change

d

79. Respiratory alkalosis can occur as a result of A) asphyxia. B) asthma. C) severe emphysema. D) hyperventilation. E) hypoventilation.

d

Questions 81 through 83 are all based on the following case study: You have just admitted Mary Roberts, a 70-year-old woman, to the hospital for GI bleeding. Her blood pressure is 130/80, pulse 80/min and irregular, respirations 18/min, and temperature 99.2. Mrs. Roberts denies pain at this time although she appears anxious and very pale. Her medical history includes lung cancer that was diagnosed two weeks ago, peptic ulcer disease with reflux esophagitis, and "fluid retention". Admission lab work shows a plasma Na+ of 152 mEq/L and K+ of 2.8 mEq/L.

...

10. One difference between the plasma and interstitial fluid is that the plasma has significantly more _____ than interstitial fluid. A) protein B) bicarbonate C) chloride D) water volume E) hydrogen ions

a

12. Water moves back and forth across the plasma membrane by the process of A) osmosis. B) filtration. C) facilitated diffusion. D) active transport. E) endocytosis.

a

13. The cation that plays a major role in determining the osmotic pressure of the plasma is A) sodium. B) potassium. C) chloride. D) phosphate. E) hydrogen ion.

a

2. Which of the following fluid compartments contains the smallest volume of water? A) plasma B) interstitial compartment C) intracellular compartment D) extracellular compartment E) cytoplasm

a

41. Most of the calcium in the body is in the A) bones. B) plasma. C) kidneys. D) GI tract. E) extracellular fluid.

a

15. When aldosterone is absent, sodium reabsorption in the nephron is A) greatly increased. B) greatly decreased. C) unchanged.

b

16. As the rate of sweat production increases, the amount of sodium lost in the urine A) increases. B) decreases. C) remains the same.

b

18. Renin is released by the A) lungs. B) kidney. C) spleen. D) liver. E) pancreas.

b

27. Increased ADH secretion could be stimulated by which of the following situations? A) increased renal blood flow B) increased blood osmolality C) increased atrial natriuretic hormone production D) increased blood pressure E) decreased blood osmolality

b

32. Decreased extracellular potassium levels cause A) cells to become more excitable. B) hyperpolarization of cell membranes. C) more action potentials to be generated. D) increased permeability of cell membranes. E) hypopolarization of cell membranes.

b

35. Oversecretion of aldosterone causes A) decreased secretion of calcium by the kidney. B) increased secretion of potassium by the kidney. C) decreased reabsorption of sodium by the kidney. D) increased reabsorption of phosphate ions by the kidney. E) decreased secretion of potassium by the kidney.

b

36. Aldosterone secretion may be stimulated by A) ADH. B) elevated potassium levels. C) excess water intake. D) elevated sodium levels. E) low potassium levels.

b

47. Stimulus for the secretion of parathyroid hormone is a decrease in serum A) potassium levels. B) calcium levels. C) calcitonin levels. D) phosphate levels. E) sodium levels.

b

49. The main regulator of serum phosphate levels is a transport process in the A) liver. B) kidneys. C) pancreas. D) small intestine. E) large intestine.

b

55. Under normal conditions, most water loss from the body is through the A) skin. B) kidneys. C) lungs. D) GI tract. E) sweat.

b

66. Body fluid pH will rise dramatically when A) sodium is excreted by the kidney. B) large amounts of bicarbonate are ingested. C) carbonic acid is formed. D) the respiratory rate decreases. E) carbon dioxide levels increase.

b

69. Which of the following terms does not belong with the other three? A) acidosis B) pH increases C) H+ ion concentration increases D) carbonic acid levels increase E) pH decreases

b

75. Hyposecretion of aldosterone would lead to A) increased secretion of hydrogen ions. B) decreased secretion of hydrogen ions. C) no change in secretion of hydrogen ions.

b

78. Ingesting large amounts of sodium bicarbonate can lead to A) metabolic acidosis. B) metabolic alkalosis. C) respiratory acidosis. D) respiratory alkalosis. E) none of the above

b

8. The predominant extracellular cation is A) bicarbonate. B) sodium. C) chloride. D) potassium. E) hydrogen ion.

b

80. Prolonged vomiting of stomach contents will result in A) metabolic acidosis. B) metabolic alkalosis. C) respiratory acidosis. D) respiratory alkalosis. E) none of the above

b

81. Which of the following regulatory mechanisms would be stimulated as a result of the increased osmolality that results from a Na+ level of 152 mEq/L? A) increased urine output B) an increased release of ADH C) an increase in renin production D) an increase in the secretion of aldosterone E) a decreased release of ADH

b

83. The K+ level of 2.8 mEq/L indicates hypokalemia. Low plasma K+ levels will cause A) thirst. B) muscle weakness. C) increased body temperature. D) tremors, tetany, and convulsions. E) paralysis.

b

1. Which of the following fluid compartments contains the largest volume of water? A) plasma B) interstitial compartment C) intracellular compartment D) extracellular compartment E) lymph

c

17. Receptors sensitive to changes in the osmolality of extracellular fluid are the A) baroreceptors. B) chemoreceptors. C) osmoreceptors. D) pressoreceptors. E) proprioreceptors.

c

19. Which of the following events occurs last? A) release of renin by the kidney B) release of aldosterone by the adrenal cortex C) sodium reabsorption by the kidney tubules D) angiotensinogen angiotensin I E) angiotensin I angiotensin II

c

20. The primary regulator of plasma sodium concentration is A) renin. B) aldosterone. C) antidiuretic hormone (ADH). D) atrial natriuretic hormone. E) insulin.

c

50. A major complication of thyroid surgery is the accidental damaging or removal of the parathyroid glands. This damage or removal of the parathyroid glands can result in A) increased sodium retention. B) increased plasma volume. C) decreased plasma calcium. D) delayed healing. E) increased plasma calcium.

c

53. The sensation of thirst results from A) an increase in the plasma volume. B) hypertension (increased blood pressure). C) stimulation of osmoreceptor cells in the hypothalamus. D) a decrease in the osmolality of the extracellular fluid. E) stimulation of baroreceptors.

c

57. Sensible perspiration A) contains only water. B) is water lost through simple evaporation. C) is secreted by the sweat glands. D) is invisible on the skin. E) is secreted by salivary glands.

c

6. Extracellular fluid has a A) higher protein content than intracellular fluid. B) higher potassium content that intracellular fluid. C) higher sodium content than intracellular fluid. D) higher magnesium content than intracellular fluid E) higher number of large organic molecules than intracellular fluid.

c

61. pH A) increases with acidity. B) is measured on a scale of 0 to 10. C) is a measure of the hydrogen ion concentration. D) reflects sodium content of body fluids. E) is not related to amounts of carbon dioxide in the body.

c

71. In renal compensation of acidosis, A) H+ secretion decreases; bicarbonate excretion increases. B) H+ secretion decreases; bicarbonate reabsorption increases. C) H+ secretion increases; bicarbonate reabsorption increases. D) H+ secretion increases; bicarbonate excretion increases. E) H+ secretion decreases; bicarbonate excretion decreases.

c

73. The normal pH for blood plasma is A) 7.00. B) 7.25. C) 7.40. D) 7.55. E) 7.60.

c

74. Once alkalosis has occurred, which of the following would you expect to happen? A) increased respiratory rate B) a plasma pH less than 7.40 C) retention of hydrogen ions by the kidney D) increased renal reabsorption of bicarbonate ions E) secretion of hydrogen ions by the kidney

c

60. A person working in the hot sun loses the greatest amount of water from the A) lungs. B) urine. C) mouth. D) skin. E) GI tract.

d

25. Elevated blood pressure under resting conditions results in increased urinary output because A) baroreceptors signal the hypothalamus to increase ADH secretion. B) elevated blood pressure stimulates renin secretion. C) the amount of angiotensin II formed is increased. D) aldosterone levels increase. E) baroreceptors signal the hypothalamus to decrease ADH secretion.

e

38. Which of the following will the body begin to do in order to compensate for hyperkalemia? A) vasoconstriction of blood vessels B) increase ADH secretion C) decrease aldosterone secretion D) increase the release of atrial natriuretic hormone E) increase aldosterone secretion

e

44. Calcium's roles in the body include A) bone health. B) muscle contraction. C) blood clotting. D) action potentials in heart muscle. E) all of the above

e

21. Which of the following is most likely to happen to a group of students who relax by drinking a pitcher of their favorite beverage? A) an increase in urine volume B) an increase in urine osmolality C) an increase in ADH production D) increased aldosterone secretion E) a decrease in urine volume

a

28. Atrial natriuretic hormone increases A) urine volume. B) ADH secretion. C) aldosterone secretion. D) the reabsorption of sodium ions. E) blood volume.

a

4. Which of the following individuals would have the largest percentage of their bodyweight as water? A) a small 7-year-old female B) a lean 35-year-old male athlete C) a chunky 52-year-old male athlete D) a healthy 88-year-old male E) an adult female marathon runner

a

40. Which of the following is correctly matched? A) alkalosis - hypokalemia B) cell destruction - hypokalemia C) increased secretion of aldosterone - hyperkalemia D) overuse of diuretics - hyperkalemia E) acidosis - hypokalemia

a

45. An increase in parathyroid hormone levels results in A) increased rate of bone resorption. B) increased rate of vitamin D degradation. C) increased concentration of potassium ions in the urine. D) increased rate of calcium ion excretion by the kidneys. E) decreased levels of blood calcium.

a

5. Which of the following people would be most severely affected by prolonged vomiting? A) 3-year-old male B) 15-year-old male C) 35-year-old male D) 35-year-old female E) 50-year-old male

a

52. Increased osmolality of the ECF A) increases thirst. B) inhibits ADH. C) increases renin secretion. D) increases aldosterone secretion. E) decreases thirst.

a

54. Angiotensin II increases blood volume by stimulating A) thirst. B) vasodilatation. C) water movement into the cells. D) renal excretion of sodium. E) ADH production.

a

59. In which of the following situations does one see large volumes of dilute urine produced? A) ADH levels decrease B) renin levels increase C) aldosterone levels increase D) parathyroid hormone levels decrease E) ADH levels increase.

a

62. Which of the following substances releases hydrogen ions into a solution? A) acids B) bases C) salts D) glucose E) water

a

63. Chemicals that function to minimize changes in the pH of body fluids are called A) buffers. B) inhibitors. C) accelerators. D) activators. E) stabilizers.

a

70. Mr. I.M.A. Wreck's plasma pH is 7.2. Which of the following indicates that the body is attempting to compensate and return the body pH to normal? A) an increase in respiration rate B) a decrease in respiration rate C) no change in respiration rate

a

76. When normal buffer mechanisms are overwhelmed by excessive numbers of hydrogen ions, which of the following will result? A) acidosis B) alkalosis C) neither of these

a

82. The increase in extracellular osmolality would cause A) water to move out of the cells. B) water to move into the cells. C) no change in the net movement of water into or out of the cells.

a

84. Bob Trotts has an enteropathogenic E. coli infection resulting in severe diarrhea for 2 days. This could produce which of the following. 1. acidosis 2. alkalosis 3. increased respiration 4. decreased respiration 5. increased ADH secretion 6. increased renin secretion 7. increased urine concentration A) 1, 3, 5, 6, 7 B) 2, 4, 5, 6, 7 C) 1, 3, 6 D) 2, 4, 5, 7 E) 1, 4, 5, 7

a

9. The distribution of sodium and potassium ions between intracellular and extracellular compartments is A) potassium mainly intracellular; sodium mainly in extracellular. B) sodium mainly intracellular; potassium mainly in extracellular. C) little of either intracellular but large amounts of both extracellular. D) equal amounts of both ions, in both intracellular and extracellular fluids. E) none of the above

a

14. The major route of excretion for sodium ions (under normal conditions) is the A) skin. B) kidney. C) GI tract. D) adrenal cortex. E) sweat.

b

67. As a result of hyperventilation, A) the body pH decreases. B) the plasma PCO2 level decreases. C) the kidney will increase the rate of hydrogen ion excretion. D) more bicarbonate ions are added to the plasma. E) the plasma PCO2 level increases.

b

22. Antidiuretic hormone (ADH) A) increases plasma osmolality. B) is secreted by the anterior pituitary. C) increases water reabsorption in the kidneys. D) causes the production of a large volume of urine. E) increases urine volume.

c

24. The stimulus for secretion of atrial natriuretic hormone is increased A) blood osmolality. B) aldosterone production. C) blood pressure in atria of heart. D) blood pressure in kidney's afferent arterioles. E) blood pressure in the ventricles of the heart.

c

30. Oversecretion of aldosterone causes A) hyperkalemia. B) hypercalcemia. C) hypernatremia. D) increased urine volume. E) hyponatremia.

c

33. Which of the following statements concerning potassium ions is false? A) An increase in the extracellular potassium ion concentration leads to depolarization. B) Potassium ions are secreted into the nephron by the distal convoluted tubule. C) When aldosterone levels are high, potassium secretion is low. D) Aldosterone secretion is stimulated by high blood levels of potassium ions. E) none of the above are false

c

39. Hyperkalemia is defined as A) excess excitability of kalems. B) reduction of plasma calcium level. C) increase in plasma potassium level. D) increase in plasma sodium level. E) decrease in plasma potassium level.

c

43. Calcium balance is influenced by A) ADH and parathyroid hormone levels. B) ADH and aldosterone levels. C) parathyroid hormone and vitamin D levels. D) aldosterone and parathyroid hormone levels. E) insulin and glucagon

c

46. Adequate calcium absorption from the GI tract depends on A) serum K levels. B) serum calcitonin levels. C) adequate amounts of vitamin D. D) the osmolality of the extracellular fluid. E) adequate amounts of vitamin C.

c

48. Parathyroid hormone effects the A) bones, heart, and blood. B) kidney, liver, and spleen. C) intestine, kidneys, and bone. D) liver, stomach, and small intestine. E) stomach, pancreas, and bone

c

77. A falling blood pH and a rising concentration of carbon dioxide due to emphysema, indicate A) metabolic acidosis. B) metabolic alkalosis. C) respiratory acidosis. D) respiratory alkalosis. E) none of the above

c

11. Serum electrolyte concentrations are most often expressed as A) mg %. B) mmHg. C) mg/dl. D) mEq/L. E) none of the above

d

23. A decrease in plasma osmolality would increase A) ADH production. B) plasma sodium levels. C) renin production. D) urine production. E) thirst.

d

26. You've been working outside in the hot sun and are dripping wet with sweat. Your fluid intake has been minimal as you have been too busy to stop and get a drink. You would expect A) your blood osmolality to be low. B) an increase in the production of urine. C) aldosterone levels to decrease. D) ADH levels to increase. E) ADH levels to decrease.

d

29. Which of the following would be expected to cause hyponatremia? A) high intake of sodium B) increased aldosterone production C) increased urine output D) increased ADH production E) decreased ADH production

d

3. Synovial fluid is a part of which of the following fluid compartments? A) plasma B) interstitial C) intracellular D) extracellular E) cytoplasm

d

31. Chloride ions A) are cations. B) are found only inside cells. C) are part of the DNA molecule. D) are lost when vomiting. E) are not found in extracellular fluid.

d

34. Potassium levels in the body are regulated by A) ADH. B) PTH. C) calcitonin. D) aldosterone. E) insulin.

d

37. The most common cause of hyperkalemia is A) vomiting. B) increased dietary intake. C) increased urinary output. D) cellular injury or death. E) diarrhea.

d

58. Loss of a large volume of sweat will A) decrease the hematocrit. B) decrease ADH production. C) increase the blood pressure. D) increase the osmolality of body fluids. E) decrease the osmolality of body fluids.

d

85. Azetazolamide (Diamox) is a diuretic. It functions by blocking the activity of carbonic anhydrase inside kidney tubule cells. This slows the formation of carbonic acid. By slowing the formation of hydrogen ions in the cells of the tubule, sodium reabsorption is also slowed. This results in the diuretic effect. Select from the following list the possible side-effects of Azetazolamide. 1. acidosis 2. reduced movement of bicarbonate ion into the plasma 3. an alkaline urine is produced 4. respiration increases A) 1, 4 B) 2, 3 C) 1, 2, 3 D) 2, 3, 4 E) 1, 2, 3, 4

e