Physiology MCQ

Question 1

1. Concerning renal ontogeny:
   A. the pronephros is a transitory kidney present during the embryonic life of all vertebrates
   B. the mesonephros is a functional yet transitory kidney during intrauterine life of mammals
   C. a main morphological difference between the metanephros (permanent kidney) and the mesonephros, is the development of the loop of Henle
   D. A and C are correct
   E. all are correct

Answer 1

e

Question 2

2. The main barrier precluding the free passage of albumin across the glomerular capillary walls is formed by:
   A. the fenestrated glomerular endothelium
   B. anionic proteoglycan clusters within the glomerular basement membrane
   C. the filtration slits in between visceral epithelial cells (podocytes)
   D. none are correct
   E. all are correct

Answer 2

b

Question 3

3. Concerning the measurement of renal plasma flow (RPF) and glomerular filtration rate(GFR):
   A. inulin is a good GFR marker because it is freely filtered in the glomeruli and it is not reabsorbed, or secreted, by the renal tubules
   B. inulin concentration in the proximal tubule’s lumen increases progressively as water is reabsorbed in the segment of the nephron
   C. PAH (para-amino-hippuric acid)is a good marker of renal plasma flow because it is freely filtered and is rapidly secreted by the proximal tubule; as a result very little PAH reaches the renal vein
   D. A and C are correct
   E. all are correct

Answer 3

e

Question 4

4. Concerning the functional histology of the kidney:
   A. the superficial nephrons have short loops of Henle; thus, they have a low capacity to reabsorb salt (salt losing nephrons)
   B. the deep nephrons have long loops of Henle; thus they have a high capacity to reabsorb salt and water
   C. in dehydration, the blood flow to deep nephrons tends to increase
   D. A and C are correct
   E. all are correct

Answer 4

e

Question 5

5. The following factor(s) tend(s) to INCREASE the rate of glomerular filtration (GFR):
   A. decreased albumin concentration in plasma
   B. vasodilation of the afferent (pre-glomerular) arteriole
   C. vasoconstriction of the efferent (post-glomerular) arteriole
   D. A and C are correct
   E. all are correct

Answer 5

e

Question 6

6. The following factor(s) tend(s) to INCREASE the rate of glomerular filtration (GFR):
   A. sympathetic stimulation (norepinephrine) of the afferent arteriole
   B. obstruction of the renal tubules, ureter or urethra
   C. vasodilation of the efferent arteriole
   D. none are correct
   E. all are correct

Answer 6

d

Question 7

7. Concerning the function of the glomerular mesangial cells:
   A. mesangial cells can contract and cause some decrease in total glomerular filtration area
   B. mesangial cells play a major role in systemic angiotensin II production
   C. mesangial cells are phagocytic and play a role in the clearing of proteins and immune-deposits entrapped in the mesangium
   D. A and C are correct
   E. all are correct

Answer 7

d

Question 8

8. Concerning the function of the proximal tubule:
   A. most of the glomerular ultrafiltrate is reabsorbed in the proximal tubule in an iso-osmotic fashion.
   B. the concentration of PAH doesn’t change much along the length of the proximal tubule
   C. under normal conditions, most of the filtered glucose and bicarbonate are reabsorbed in the proximal tubule
   D. A and C are correct
   E. all are correct

Answer 8

d

Question 9

9. Concerning metabolic energy (at production) for renal transport:
   A. the main substrate for proximal tubule is glucose
   B. the cortical PO2 is about 10 mmHg
   C. the papillary tissues normally generate ATP via oxidative metabolism
   D. A and C are correct
   E. all are correct

Answer 9

b

Question 10

10. Concerning water reabsorption by the proximal tubule:
    A. main driving forces for water reabsorption in the proximal tubule are solute uptake and oncotic pressure in peritubular capillaries
    B. a significant amount of water uptake in the proximal tubule is dependent on sodium uptake by the Na/H antiports present in their luminal membrane
    C. aquaporine-I (water channels) are abundantly present in the cellular membranes of proximal tubule cells
    D. A and C are correct
    E. all are correct

Answer 10

e

Question 11

11. Concerning the THICK loop of Henle:
    A. the thick segment of the loop has a very powerful Na/K/2Cl pump that moves salt from the tubular lumen into the peritubular space
    B. water and urea move freely across the epithelium of the thick ascending segment of the loop
    C. following the administration of furosemide (lasix) large volumes of diluted urine are produced
    D. A and C are correct
    E. all are correct

Answer 11

d

Question 12

12. Concerning urinary concentration:
    A. the thick loop of Henle generates most of the osmotic gradient needed for reabsorption of water in the collecting duct
    B. the tubular urine that reaches the collecting duct is generally hypotonic with respect to plasma
    C. in the absence of ADH, urine is not concentrated along the length of the collecting duct
    D. A and C are correct
    E. all are correct

Answer 12

e

Question 13

13. Concerning the transport of urea in the different segments of the nephron:
    A. main tubular urea sound is the plasma via the glomerular ultrafiltrate
    B. the urea concentration in the lumen of the cortical collecting ducts increases as water is reabsorbed
    C. the thin loop of Henle and the medullary collecting duct are permeable to urea
    D. A and C are correct
    E. all are correct

Answer 13

e

Question 14

14. Concerning the macula densa:
    A. the macula densa senses the total amount of sodium chloride (sodium chloride concentration times volume) of tubular urine being delivered by the loop of Henle into the distal convoluted tubule
    B. if the delivery of sodium chloride is lower than normal the macula densa signals the afferent arteriole (pre-glomerular) to release renin
    C. renin release causes intravascular angiotensin formation and indirectly aldosterone release
    D. A and C are correct
    E. all are correct

Answer 14

e

Question 15

15. Concerning angiotensin II:
    A. the exocrine renin-angiotensin-aldosterone system includes angiotensinogen production by the liver, renin secretion by the juxtaglomerular apparatus and angiotensin-converting enzyme present at the luminal surface of endothelial cells
    B. aldosterone, but not AII, stimulate thirst and salt appetite
    C. angiotensin II induces marked increases in sodium reabsorption by the loop of Henle and the collecting duct
    D. A and C are correct
    E. all are correct

Answer 15

a

Question 16

16. Within an hour following intravenous angiotensin II infusion, the following is(are) clinically evident:
    A. increased sodium uptake in the proximal tubular epithelium
    B. systemic vasoconstriction
    C. increased plasma aldosterone
    D. A and C are correct
    E. all are correct

Answer 16

e

Question 17

17. Within eight hours following large intravenous aldosterone infusion the following is(are)clinically evident:
    A. unchanged sodium reabsorption by the collecting duct
    B. decreased potassium and hydrogen excretion in urine
    C. hypernatremia (high sodium in plasma), hypokalemia (low potassium in plasma) and alkalosis (low hydrogen ion activity in plasma)
    D. A and C are correct
    E. all are correct

Answer 17

c

Question 18

18. Concerning arterial blood pressure regulation:
    A. prostaglandins and dopamine and bradykinin are vasodilators
    B. ADH, angiotensin II and epinephrine are vasoconstrictors
    C. the vasodilator/vasoconstrictor ratio that regulates total peripheral resistance plus cardiac stroke volume and heart rate are determinants of blood pressure
    D. all are correct
    E. none are correct

Answer 18

e

Question 19

19. Concerning cell volume regulation:
    A. the Na/H and Cl/HCO3 antiports are involved in hypertonic cell volume regulation
    B. rapid efflux of cytoplasmic water is followed by volume regulatory KCL efflux
    C. KCL efflux is involved in hypotonic cell volume regulation
    D. A and C are correct
    E. all are correct

Answer 19

d

Question 20

20. Intravenous administration of 1.5 liters of isotonic Ringer’s solution to a healthy adult could cause:
    A. increased cardiac output and renal blood flow
    B. increased GFR
    C. increased atrial natriuretic peptide and decreased renin in plasma
    D. A and C are correct
    E. all are correct

Answer 20

e

Question 21

21. Renin
A. Increased H2O reabsorption
B. Decreased sodium reabsorption
C. AII formation
D. Increased sodium reabsorption
E. Decreased phosphate reabsorption

Answer 21

c

Question 22

22. Atrial natriuretic peptide
A. Increased H2O reabsorption
B. Decreased sodium reabsorption
C. AII formation
D. Increased sodium reabsorption
E. Decreased phosphate reabsorption

Answer 22

b

Question 23

23. ADH
A. Increased H2O reabsorption
B. Decreased sodium reabsorption
C. AII formation
D. Increased sodium reabsorption
E. Decreased phosphate reabsorption

Answer 23

a

Question 24

24. AII
A. Increased H2O reabsorption
B. Decreased sodium reabsorption
C. AII formation
D. Increased sodium reabsorption
E. Decreased phosphate reabsorption

Answer 24

d

Question 25

``` 25. PTH A. Increased H2O reabsorption B. Decreased sodium reabsorption C. AII formation D. Increased sodium reabsorption E. Decreased phosphate reabsorption ```

Answer 25

e

Question 26

26. Which one of the following is correct about nonvolatile acids. A. they are not essential to eliminate from the body B. we generate much greater amounts of nonvolatile than volatile acids C. they are fully buffered by bone D. they are products of intermediary metabolism and protein degradation E. they are eliminated by the lungs

Answer 26

d

Question 27

27. All of the following occur within one hour of eating a large acid load EXCEPT: A. the acid load is immediately buffered by intracellular proteins and phosphates as well as extracellular bicarbonate B. the lungs will begin eliminating CO2 generated as a result of the acid load C. the kidney will eliminate all the nonvolatile acids and regenerate bicarbonate to replace all the bicarbonate used in buffering D. hemoglobin will buffer some of the protons

Answer 27

c

Question 28

``` 28. If the pH is 7.60 (H+ concentration = 25 nEq/L) and the pCO2 is 40 mmHg, what is the HCO3- concentration (in mEq/liter). A. 10 B. 20 C. 30 D. 40 ```

Answer 28

d

Question 29

29. A patient takes a drug overdose and becomes comatose. His blood pCO2 was 40 mmHg ten minutes ago, but you discover it is now 80 mmHg. Which one of the following statements about this patient is correct. A. the pH of his CSF is likely to fall more slowly than the pH of his blood B. the pH of his blood is likely to fall more slowly than the pH of his CSF C. the pH of the blood and CSF will not change because he will rapidly eliminate bicarbonate in the urine in response to the rise in pCO2 D. the pH of the blood and CSF will change to a similar degree in this time period

Answer 29

b

Question 30

30. Which one of the following statements is true about the proximal tubule. A. the Na+/K+ ATPase drives sodium into the cell from the urine side of the tubule B. Na+/H+ exchange is largely the mechanism by which hydrogen ion secretion occurs C. bicarbonate reabsorption is independent of carbonic anhydrase activity D. the pH in the lumen of the proximal tubule can reach as low as about 5.0

Answer 30

b

Question 31

31. A patient ingests antifreeze and needs to eliminate the ingested acid. Renal elimination of the protons in this excess acid is primarily accomplished by which of the following mechanisms. A. increased urinary ammonium excretion B. increased urinary excretion of phosphates C. hyperventilation D. increased urinary free hydrogen ion concentration E. increased urinary sulfate excretion

Answer 31

a

Question 32

32. Renal ammonium ion excretion is increased by aldosterone, elevated blood pCO2 and acidemia A. true B. false

Answer 32

a

Question 33

33. Which one of the following statements is correct with regard to net collecting duct hydrogen ion secretion. A. it is decreased by increased renal production of ammonia B. it is increased by increased reabsorption of sodium through the apical sodium channel C. it is not affected by the presence or absence of titratable acids D. aldosterone does not modify collecting duct hydrogen ion secretion

Answer 33

b