On the Scantron answer sheet, completely blacken the bubble (using a number 2 pencil) in the “test form” field indicating that this is test form A. Then, indicate your responses by filling in the bubble corresponding to the one lettered item that best answers each question or completes each statement. Correct responses are highlighted in red. 1. Which of the following statements is FALSE? A Contraction of podocyte foot processes will decrease Kf, an effect that will tend to increase GFR. B Glomerular capillary blood pressure is much higher than peritubular capillary the blood pressure. C Mesangial cells act to counterbalance the fluid dynamic forces within the glomerular capillaries. D In the peritubular capillaries, the balance between plasma hydrostatic and oncotic forces is such that
2. Which of the following statements about the glomerular capillary wall is FALSE? A The basement membrane is more permeable to large anionic solutes than to large cationic solutes. B The filtered fluid passes through the slit pores of podocyte foot processes. C The glomerular capillary endothelium is highly fenestrated. D The glomerular capillary wall consists of three distinct layers.
3. Which of the following statements is FALSE? A
Constriction of the afferent arteriole will result in parallel reductions in RBF and GFR.
B Increased renal sympathetic nerve activity will result in a rise in filtration fraction. C Atrial natriuretic peptide acts to constrict the afferent arteriole. D A rise in the Cl concentration at the macula densa will trigger a constriction of the afferent arteriole.
4. If RPF is 600 mL/min and the filtration fraction is 20%, what is GFR? A B 120 mL/min
5. Regarding the proximal tubule, which of the following statements is FALSE? A
Water permeability is very high, and the osmolarity of the tubular fluid is essentially the same as that of
B Na+ transport by the sodium-hydrogen exchanger is constant. C Net fluid reabsorption increases when peritubular capillary oncotic pressure rises.
Many essential solutes (e.g., sugars, amino acids) enter the tubular cells via sodium-linked secondary
6. Which of the following is the most important apical membrane transport process that moves Na+ from the
tubular fluid into thick-ascending limb cells?
A active Na+ transport by Na+,K+-ATPase (sodium pump) B Na+-linked glucose cotransport C furosemide-inhibitable Na+,K+,2 Cl-cotransporter (NKCC) D passive diffusion through apical-membrane Na+ channels
The quiz continues on the back…
7. The action of ADH on the cells of the distal tubule and collecting duct involves which of the following steps?
A ADH binding to basolateral membrane receptors, with subsequent stimulation of cAMP production B fusion of cytosolic vesicles with the basolateral membrane C cAMP activation of a protein kinase D Both A and C.
8. The cellular actions of aldosterone in the distal tubule and collecting ducts include which of the following?
A aldosterone binding to a membrane-bound receptor located on the basolateral membrane B induction of synthesis of Na+ and K+ channels, and the Na+,K+-ATPase (sodium pump) C increased cAMP levels in the cytosol D Both A and C.
9. A person is infused with PAH. After equilibration, UPAH is 200 μg/mL, PPAH is 2 μg/mL, and urine flow is
A 250 mL/min B 250 μg/min C 400 mL/min D 1000 mL/min
10. Using the information on the graph on the right, what can you
conclude about the renal handling of this freely filtered substance?
A It is subjected to net secretion with a Tm of 30 mg/min. B It is subjected to net secretion with a Tm of 10 mg/min. C It is subjected to net reabsorption with a Tm of 0.2 mg/mL. D The transport is not Tm limited.
11. In a single nephron, Kf is 2.5 nL/(minmmHg), Pg is 55 mmHg, Pt is 10 mmHg, mean Πg is 25 mmHg,
Πt is zero (Note: subscript “g” refers to glomerular capillary, and subscript “t” refers to tubular fluid).
A 50 nL/min C 110 nL/min D None of the above.
12. The syndrome of pseudohypoaldosteronism is caused by genetic mutations in the Na+ channels in the apical
membrane in principal cells in the distal tubule and collecting ducts. The mutant channels have markedly
lower Na+ permeability. In a patient exhibiting this syndrome, which of the following symptoms would
NOT be expected? A elevated renal excretion of sodium B reduced extracellular volume C hypotension D low plasma aldosterone levels Did you remember to fill the “A” bubble in the Test Form field of your answer sheet?
Asian J. Exp. Sci., Vol. 21, No. 2, 2007, 435-443 Intra and Interspecies Variations among Environmental Klebsiella Isolates Anjana Sharma*, Susheel Kumar Singh and Sunita Patra Bacteriology Laboratory, Department of P.G. Studies and Research in Biological Science, R.D. University, Jabalpur (M.P.) 482001, India Abstract : Majority of the study of Klebsiella is restricted to clinical
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