Example Questions from Lecture Flashcards

1
Q

Renal autoregulation refers to the relative constancy of GFR and renal blood flow. A decrease in arterial pressure and glomerular filtration rate ultimately leads to a reduction in the concentraiton of sodium ions at the macula densa. This results in which of the following responses that ultimately restores GFR?

A. Release of renin by the juxtaglomerular apparatus

B. Release of endothelin by the glomerular capillaries

C. Release of nitric oxide by the vasa recta endothelium

D. Release of angiotensin II by the juxtaglomerular apparatus

A

A. Release of renin by the juxtaglomerular apparatus

Lecture 17 - Micturition and Glomerular Filtration

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2
Q

GFR is determined by the net filtration pressure and the glomerular capillary filtration coefficient. Which of the following factors has the greatest effect on increasing GFR?

A. Glomerular capillary colloid osmotic pressure

B. Bowman’s capsule hydrostatic pressure

C. Bowman’s capsule colloid osmotic pressure

D. Glomerular hydrostatic pressure

A

D. Glomerular hydrostatic pressure

Lecture 17 - Micturition and Glomerular Filtration

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3
Q

Minimum change disease occurs when the negative charges on the filtration membrane of the glomerulus are not present. What abnormality in the urine would be expected under these conditions?

A. Urine would contain numerous red blood cells

B. Urine would contain excess albumin

C. Urine would contain excess sodium and chloride

D. Urine wold be less concentrated

A

B. Urine would contain excess albumin

Lecture 17 - Micturition and Glomerular Filtration

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4
Q

A number of hormones are involved in the control of glomerular filtration rate. Which of the following preferentialy constricts the efferent arterioles but has little to no effect on the afferent arterioles?

A. Bradykinin

B. Angiotensin II

C. Endothelial-derived nitric oxide

D. Endothelin

A

B. Angiotensin II

Lecture 17 - Micturition and Glomerular Filtration

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5
Q

Which of the following, in liters/day, represents the GFR in the average adult human.

A. 3

B. 125

C. 180

D. 360

A

C. 180

Lecture 17 - Micturition and Glomerular Filtration

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6
Q

An increase in which of the following factors will result in a decrease in glomerular hydrostatic pressure?

A. Arterial pressure

B. Afferent arteriolar pressure

C. Efferent arteriolar pressure

D. Both B and C

E. All of the above

A

B. Afferent arteriolar pressure

Lecture 17 - Micturition and Glomerular Filtration

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7
Q

Approximately how much of the total cardiac output is received by the kidneys?

A. 25%

B. 50%

C. 75%

D. 100%

A

A. 25%

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8
Q

The macula densa is found in which of the following parts of the renal tubule?

A. Proximal convoluted tubule

B. Thin descending limb of Hinle

C. Thick ascending limb of Hinle

D. Distal convoluted tubule

A

D. Distal convoluted tubule

Lecture 17 - Micturition and Glomerular Filtration

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9
Q

The thin descending loop of Henle is highly permeable to which of the following?

A. Sodium

B. Water

C. Urea

D. Amino acids

A

B. Water

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10
Q

Aldosterone is an important regulator of sodium reabsorption and potassium secretion; one of its main targets is…?

A. Podocytes

B. Principle cells

C. Intercalated cells

D. Cells of the macula densa

A

B. Principle cells

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11
Q

Which of the following cells play a major role in the secretion of potassium?

A. Intercalated cells

B. Principal cells

C. Chief cells

D. Podocytes

A

B. Principal cells

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12
Q

Most potassium reabsorption occurs at which of the following sites?

A. Ascending loop of Henle

B. Distal convoluted tubule

C. Proximal convoluted tubule

D. Collecting duct

A

C. Proximal convoluted tubule

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13
Q

Primary active hydrogen secretion involves a hydrogen-transporting ATPase. It occurs in which of the following parts of the renal tubule?

A. Descending limb of Henle

B. Ascending limb of Henle

C. Late distal tubules in intercalated cells

D. Early collecting tubules in principal cells

A

C. Late distal tubules in intercalated cells

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14
Q

Which of the following reflects the amount of urine that the kidneys can excrete per day when there is a large excess of water?

A. 180 liters

B. 75 liters

C. 20 liters

D. 4 liters

A

C. 20 liters

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15
Q

ADH acts on which of the following regions of the nephron?

A. Proximal convoluted tubule

B. Descending loop of Henle

C. Ascending loop of Henle

D. Distal convoluted tubule

A

D. Distal convoluted tubule

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16
Q

Which of the following reflects the maximum urine concentration that can be produced by the kidneys?

A. 6000-7000 mOsm/L

B. 5500-6000 mOsm/L

C. 1200-1400 mOsm/L

D. 2000-2400 mOsm/L

A

C. 1200-1400 mOsm/L

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17
Q

Osmoreceptor cells are located in which of the following regions?

A. Adjacent to the carotid bodies

B. In the macula densa

C. In the anterior part of the third ventricle

D. In the distal collecting ducts

A

C. In the anterior part of the third ventricle

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18
Q

Which of the following segment of the nephron is NOT permeable to water?

A. Proximal convoluted tubule in the pressence of ADH

B. Descending loop of Henle in the pressence of ADH

C. Ascending loop of Henle in the pressence of ADH

D. Distal convoluted tubule in the pressence of ADH

A

C. Ascending loop of Henle in the pressence of ADH

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19
Q

Which of the following plays a major role in stimulating potassium excretion by the kidney tubules?

A. Aldosterone

B. Angiotension II

C. Sodium ions

D. PTH

A

A. Aldosterone

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20
Q

Approximately how much of the body’s supply of calcium is stored in bone?

A. 1%

B. 47%

C. 78%

D. 99%

A

D. 99%

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21
Q

How much filtered calcium is excreted by the kidneys?

A. 1%

B. 47%

C. 78%

D. 99%

A

A. 1%

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22
Q

Which of the following cells reabsorb potassium during potassium depletion?

A. Intercalated cells

B. Principal cells

C. Chief cells

D. Podocytes

A

A. Intercalated cells

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23
Q

A high potassium intake would have which of the following effects on potassium excretion associated with increased renal tubular flow rate?

A. Potassium excretion would increase with increased tubular flow rate.

B. Potassium excretion would decrease with increased tubular flow rate.

C. There would be little effect.

D. Tubular flow rate would be decreased.

A

A. Potassium excretion would increase with increased tubular flow rate.

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24
Q

Which of the following describes a valid change in potassium distribution due to an acid-base abnormality?

A. Metabolic acidosis decreases extracellular K+ concentration

B. Metabolic alkalosis increases extracellular K+ concentration

C. Metabolic acidosis increases extracellular K+ concentration

D. Both A and B

A

C. Metabolic acidosis increases extracellular K+ concentrationV

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25
Q

Which of the following buffer systems is most important in buffering renal tubular fluid?

A. Phosphate buffer system

B. Carbonate buffer system

C. Bicarbonate buffer system

D. Hemoglobin buffer system

A

A. Phosphate buffer system

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26
Q

Compounds that dissociate incompletely into hydrogen ions and a conjugate base are members of which of the following compounds?

A. Strong acids

B. Weak acids

C. Strong bases

D. Weak bases

A

B. Weak acids

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27
Q

The bicarbonate buffer system consists of a bicarbonate salt and which of the following?

A. Weak acid

B. Strong acid

C. Weak base

D. Strong base

A

A. Weak acid

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28
Q

Which of the following buffer systems is the most important extracellular buffer system.

A. Phosphate buffer system

B. Carbonate buffer system

C. Bicarbonate buffer system

D. Hemoglobin buffer system

A

C. Bicarbonate buffer system

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29
Q

Most bicarbonate reabsorption occurs in which of the following parts of the renal tubule?

A. Proximal tubule

B. Descending limb of Henle

C. Ascending limb of Henle

D. Distal tubule

A

A. Proximal tubule

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30
Q

Which of the following occurs when a decrease in bicarbonate ion results in a decrease in the ratio of bicarbonate ion to carbon dioxide in the extracellular fluid?

A. Respiratory acidosis

B. Respiratory alakalosis

C. Metabolic acidosis

D. Metabolic alkalosis

A

C. Metabolic acidosis

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31
Q

Respiratory alkalosis due to a decrease in carbon dioxide concentration caused by hyperventilation is compensated for by which of the following mechanisms?

A. Increased ventilation rate

B. Decreased ventilation rate

C. Renal excreatoin of bicarbonate ion

D. Renal addition of new bicarbonate ion to extracellular fluid

A

C. Renal excreatoin of bicarbonate ion

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32
Q

Which of the following would be a result of increased levels of angiotensin II?

A. Decreased blood pressure

B. Increased vasoconstriction

C. Increased natriuresis

D. Decreased aldosterone levels

A

B. Increased vasoconstriction

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33
Q

A 1-sodium, 2-chloride, and 1-potassium co-transporter is found in the luminal membrane of which part of the renal tubule?

A. Proximal convoluted tubule

B. Thin descending limb of Henle

C. Thick ascending limb of Henle

D. Distal convoluted tubule

A

C. Thick ascending limb of Henle

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34
Q

If tidal volume is 0.5 liters, dead space is 0.15 liters, and breathing rate is 12 times per minute; calculate the minute ventilation.

A. 1.8 liters

B. 4.0 liters

C. 6.0 liters

D. 7.8 liters

A

C. 6.0 liters

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35
Q

The solubility of oxygen = 0.024; the solubility of carbon dioxide = 0.57. Because carbon dioxide is more soluble in water than oxygen, it will exert a partial pressure (for a given concentration) that is less than 1/20th that of oxygen. This relationship between partial pressures and solubility illustrates which of the following gas laws?

A. Henry’s

B. Boyle’s

C. Dalton’s

D. Euclid’s

A

A. Henry’s

36
Q

If tidal volume is 0.5 liters, dead space is 0.15 liters, and breathing rate is 12 times per minute; calculate the minute alveolar ventilation.

A. 1.8 liters

B. 3.5 liters

C. 4.2 liters

D. 6.0 liters

A

C. 4.2 liters

37
Q

Humidification of air in the alveoli has which of the following effects on the partial pressure of nitrogen and oxygen in the alveoli?

A. It increases the partial pressure of each of the other gases.

B. It decreases the partial pressures of each of the other gases.

C. It has no effect on the partial pressure pressures of each of the other gases.

D. It increases the partial pressure of oxygen but decreases partial pressure of nitrogen in the alveolar air.

A

B. It decreases the partial pressures of each of the other gases.

38
Q

The range in the pressure change (in cm of water) in alveolar pressure during inspiration is expressed by which of the following?

A. 0 to -1

B. -5 to -7.5

C. -7.5 to -5

D. -1 to 0

A

A. 0 to -1

39
Q

What woul be the Va/Q ratio for alveolar blood with a PO2 of 104 and a pCO2 or 40?

A. 2.5

B. 0.8

C. 0

D. Infinity

A

B. 0.8

40
Q

Which of the following would be characteristic of alveoli lacking perfusion, as in the case of a pulmonary embolism?

A. Va/Q ratio = infinity

B. Va/Q = 0

C. Blood gas concentration remains unchanged

D. Both A and C are characteristic

A

A. Va/Q ratio = infinity

41
Q

Under normal conditions at rest, which of the following patterns regarding pulmonary blood flow would be most likely?

A. Apices: zone 1; middle part of lungs: zone 1; lower part of lungs: zone 3

B. Apices: zone 2; middle part of lungs: zone 2; lower part of lungs: zone 3

C. Apices: zone 2; middle part of lungs: zone 3; lower part of lungs: zone 3

D. Apices: zone 3; middle part of lungs: zone 2; lower part of lungs: zone 1

A

C. Apices: zone 2; middle part of lungs: zone 3; lower part of lungs: zone 3

42
Q

The pulmonary circulation can be divided into two systems. Which of the following describes the system supplying the trachea, bronchial tree, and the rest of the interstitium?

A. High pressure - Low flow

B. High pressure - High flow

C. Low pressure - Low flow

D. Low pressure - High flow

A

A. High pressure - Low flow

43
Q

Which of the following represents the mean pulmonary arterial pressure?

A. 7

B. 15

C. 25

D. 125

A

B. 15

44
Q

The most common cause of pulonary edema is left sided heart failure or mitral valve disease. Pulmonary edema occurs when pulmonary capillary pressure exceeds which of the following levels?

A. 7 mmHg

B. 15 mmHg

C. 20 mmHg

D. 25 mmHg

A

D. 25 mmHg

45
Q

About 80 mEq of nonvolatile acid is formed by metabolism per day. The minimal urine hydrogen concentraiton is about 0.03 mEq/L. What would be the approximate volume of urine required if all excess hydrogen ions remained free in solution.

A. 1.5 L/day

B. 180 L/day

C. 2700L/day

D. 4500 L/day

A

C. 2700L/day

46
Q

Which of the following receptors are sensory endings (C fibers) in the alveolar wall next to the pulmonary capillaries that are sensitive to pulmonary edema?

A. Slow-adapting pulmonary stretch receptors

B. Rapidly-adapting pulmonary stretch receptors

C. J receptors

D. Hering Breuer receptors

A

C. J receptors

47
Q

Which of the following respresnts the oxygen utilization coefficient at rest?

A. 15%

B. 25%

C. 50%

D. 75%

A

B. 25%

48
Q

What is the lowest limit of pH that can be achieved in the normal kidney?

A. 6.5

B. 5.0

C. 4.5

D. 2.5

A

C. 4.5

49
Q

Which of the following factors decreases potassium uptake by cells?

A. Aldosterone

B. Metabolic acidosis

C. Insulin

D. Catecholamines

A

B. Metabolic acidosis

50
Q

A hydrogen—transporting ATPase is first encountered in which of the following parts of the renal tubule?

A. Proximal convoluted tubule

B. Descending limb of Henle

C. Ascending limb of Henle

D. Distal convoluted tubule

A

D. Distal convoluted tubule

51
Q

Normally, how much hydrogen ions must be secreted each day in order to reabsorb 4320 mEq of filtered bicarbonate?

A. 2160 mEq

B. 4320 mEq

C. 8640 mEq

D. The two processes are independent of one another

A

B. 4320 mEq

52
Q

Decreased concentrations of calcium ion in the plasma would have a direct effect on which of the following?
A. Activation of vitamin D3

B. Increase in interstitial calcium ion reabsorption

C. Increased release of parathyroid hormone

D. Release of calcium ion from bones

A

C. Increased release of parathyroid hormone

53
Q

In a normal individual, which of the following represents the transport maximum for glucose?

A. 125mg/min

B. 250 mg/min

C. 375 mg/min

D. 500 mg/min

A

C. 375 mg/min

54
Q

Which of the following represents a substance that is actively secreted into the renal tubules?

A. Urea

B. Angiotension II

C. Creatinine

D. ADP

A

C. Creatinine

55
Q

Which of the following best describes the capillary filtration coefficient?

A. Average diamerters of the glomerular capillaries.

B. Mean of the capillary pressure within the glomerulus.

C. Product of the permeability and filtering sufrace area of the glomerular capillaries.

D. Mean of the hydrostatic pressure within the glomerular capillaries.

A

C. Product of the permeability and filtering sufrace area of the glomerular capillaries.

56
Q

Which of the following is a vasodilator that may help to offset the effects of vasoconstrictors, especially on afferent arteriole?
A. Bradykinin

B. Endothelin

C. Angiotension II

D. Norepinephrine

A

A. Bradykinin

57
Q

Much of the oxygen consumed by the kidneys is related to which of the following factors?

A. High rate of glucose reabsorption

B. High rate of active sodium reabsorption

C. High rate of active potassium reabsorption

D. High rate of active amino acid reabsorption

A

B. High rate of active sodium reabsorption

58
Q

Which of the following is responsible for partial inhibition micturition except when micturition is desired?

A. Parasympathetic system

B. Sympathetic system

C. Pedendal nerves

D. Pelvic splanchinc nerves

A

C. Pedendal nerves

59
Q

Without autoregulation, a slight increase in blood pressure could increase GFR up to 225 L/day. How much would this increase urine flow (excretion).

A. 20L/day

B. 32.7 L/day

C. 46.5 L/day

D. 180 L/day

A

C. 46.5 L/day

60
Q

What is the partial pressure of oxygen in mmHg at the alveolar membrane if the percentage of oxygen in the alveoli is 20%?

A. 75

B. 122

C. 152

D. 266

A

C. 152

61
Q

Using the Flick principle for calculating the cardiac output, the pateient’s resting oxygen consumption volume should be divided by which of the following?

A. The difference between oxygen concentration in the systemic arterial blood and the systematic mixed venous blood.

B. The difference between the oxygen concentration in the systemic arterial blood and the pulmonary vein.

C. The difference between the oxygen concentraiton in the systemic mixed blood and the pulmonary vein.

D. The difference between the oxygen concentration in the systemic mixed venous blood and the pulmonary artery.

A

A. The difference between oxygen concentration in the systemic arterial blood and the systematic mixed venous blood.

62
Q

What is the glomerular filtration rate if the urine concentration rate of a substance is 125 mg/mL; the flow rate is 2 mL/min; and the plasma concentraiton of the substance is 1mg/mL?

A. 10

B. 25

C. 125

D. 250

A

D. 250

63
Q

Almost 90 percent of glucose reabsorption occurs in the early proximal tubule. Which of the following mechanisms is responsible for moving glucose from the tubular lumen into the cytoplasmic compartment?

A. Primary active transport via a glucose ATPase pump.

B. Secondary active transport via a sodium/glucose cotransporter.

C. Secondary active transport via a sodium glucose antiporter.

D. Diffusion due to concentraiton differences between tubular fluid and cytoplasm.

A

B. Secondary active transport via a sodium/glucose cotransporter.

64
Q

A 24-year old woman presents to the emergency department with severe diarrhea. When she is supine, her blood pressure is 90/60 mmHg (decreased) and her heart rate is 100 beats per minute (increased). When she is moved to a standing position, her heart rate increases to 120 beats per minute. Which of the following accounts for the further increase in heart rate upon standing?

A. Decreased total peripheral resistance

B. Increased vasoconstriction

C. Increased afterload

D. Decreased venous return

A

D. Decreased venous return

65
Q

Which of the following factors results in hypokalemia?

A. Cell lysis

B. Excess secretion of aldosterone

C. Strenuous exercise

D. Increased extracellular fluid osmolarity

A

B. Excess secretion of aldosterone

66
Q

An increase in which of the following factors will result in a decrease in glomerular hydrostatic pressure?

A. Arterial pressure

B. Afferent arteriolar pressure

C. Efferent arteriolar pressure

D. Both B and C

E. All of the above

A

B. Afferent arteriolar pressure

67
Q

Which of the following centers acts to control the “switch-off” point of the inspiratory ramp signal?

A. Dorsal respiratory group

B. Pneumotaxic center

C. Ventral respiratory group

D. Aortic body

A

B. Pneumotaxic center

68
Q

ADH (anti-diuretic hormone) is formed in the supraoptic and paraventriacular nulcei. It is secreted by specialized neurons from which of the following areas?

A. Adrenal cortex

B. Adrenal medulla

C. Anterior pituitary

D. Posterior pituitary

A

D. Posterior pituitary

69
Q

A normal 70 kg human must excrete about 600 mOsm of solute each day in order to get rid of waste products of metabolism and ions that are ingested. The maximal urine concentrating ability is 1200 mOsm/L. Which of the following represents the obligatory urine volume that must be excreted each day to get rid of metabolic waste products?

A. 1.0 L/day

B. 0.5 L/day

C. 0.3 L/day

D. 0.0 L/day

A

B. 0.5 L/day

70
Q

ADH acts on which of the following regions of the nephron?

A. Proximal convoluted tubule

B. Descending loop of Henle

C. Ascending loop of Henle

D. Distal convoluted tubule

A

D. Distal convoluted tubule

71
Q

Which of the following reflects the amount of urine that the kidneys can excrete per day when there is a large excess of water?

A. 180 liters

B. 75 liters

C. 20 liters

D. 4 liters

A

C. 20 liters

72
Q

Which of the following reflects the maximum urine concentration that can be produced by the kidneys?

A. 6000-7000 mOsm/L

B. 5500-6000 mOsm/L

C. 1200-1400 mOsm/L

D. 2000-2400 mOsm/L

A

C. 1200-1400 mOsm/L

73
Q

Because of paracellular diffusion of ions back into the tubule, what is the upper limit of the concentraiton gradient created by the countercurrent mechanism?

A. 1200 mOsm/L

B. 600 mOsm/L

C. 400 mOsm/L

D. 200 mOsm/L

A

D. 200 mOsm/L

74
Q

Osmoreceptor cells are located in which of the following regions?

A. Adjacent to carotid bodies

B. In the macula densa

C. In the anterior part of the third ventricle

D. In the distal collecting ducts

A

C. In the anterior part of the third ventricle

75
Q

Which of the following would NOT shift the oxygen-hemoglobin curve to the right and downward?

A. A decrease in pH

B. An increas in carbon dioxide

C. An increase in temperature

D. A decrease in BPG (bi-phosphoglycerate)

A

D. A decrease in BPG (bi-phosphoglycerate)

76
Q

What percentage of carbon dioxide is carried in the blood as bicarbonate?

A. 5%

B. 25%

C. 30%

D. 70%

A

D. 70%

77
Q

Which respiratory control center is primarily responsible for establishing the ramp signal during normal breathing?

A. Dorsal respiratory group

B. Pneumotaxic center

C. Ventral respiratory center

D. Carotid body

A

A. Dorsal respiratory group

78
Q

What is the source of the hormone aldosterone?

A. Juxtaglomerular cells

B. Principal cells

C. Adrenal cortex

D. Liver

A

C. Adrenal cortex

79
Q

Magnesium and calcium are reabsorbed from the tubular lumen through which of the following mechanisms?

A. Antiport with sodium ions

B. Active transport via transporters in the basal membrane

C. Paracellular transport due to positive charge in the tubular lumen

D. Paracellular transport due to negative charge in the interstitium

A

C. Paracellular transport due to positive charge in the tubular lumen

80
Q

Shrinkage of osmoreceptor cells in the anterior hypothalamus in response to an increase in extracellular fluid osmolarity leads to the release of which of the following?

A. Aldosterone

B. Angiotension I

C. Angiotension II

D. ADH

A

D. ADH

81
Q

Chemoreceptors assocaited with respiratory functions increase their rate of activity when hypoxia or hypercapnia occur.

A. TRUE

B. FALSE

A

A. TRUE

82
Q

Most of the filtered electrolytes are reabsorbed in which of the following regions of the kidney tubule?

A. Proximal convoluted tubule

B. Descending loop of Henle

C. Ascending loop of Henle

D. Early collecting duct

A

A. Proximal convoluted tubule

83
Q

The lower pH of the tubular fluid brings the operating range of the buffer closer to the pK of which of the following systems?

A. Bicarbonate

B. Phosphate

C. Carbonic acid

D. Proteins

A

B. Phosphate

84
Q

Which of the following would NOT be true regarding the Haldane efffect?

A. Binding of oxygen with hemoglobin displaces carbon dioxide from blood.

B. Binding of oxygen causes hemoglobin to become a stronger acid.

C. Increased acidity of hemoglobin causes it to release hydrogen ions.

D. Oxygen-hemoglobin dissociation curve shift to the right.

A

D. Oxygen-hemoglobin dissociation curve shift to the right.

85
Q

Which of the following must happen before filtered bicarbonate can be reabsorbed?

A. Kidneys must secrete new bicarbonate ion.

B. Kidneys must reabsorb hydrogen ions.

C. Kidneys must secrete carbonic anhydrase.

D. Filtered bicarbonate must react with secreted hydrogen ions to form carbonic acid.

A

D. Filtered bicarbonate must react with secreted hydrogen ions to form carbonic acid.

86
Q

Which of the following segments of the nephron is NOT permeable to water?

A. Proximal convoluted tubule in the pressence of ADH.

B. Descending loop of Henle in the pressence of ADH.

C. Ascending loop of Henle in the presence of ADH.

D. Distal convolute tubule in the pressence of ADH.

A

C. Ascending loop of Henle in the presence of ADH.