DBT BET JRF 2016 Section A Questions and Answers

11. Statins are very effective against hypercholesterolemia, a major cause of atherosclerosis. These drugs reduce plasma cholesterol levels by

(A) Preventing absorption of cholesterol from the intestine.

(B) Increasing the excretion of cholesterol from the body via conversion to bile acids.

(C) Inhibiting the conversion of 3-hydroxy-3-methylglutaryl-CoA to mevalonate in the pathway for cholesterol biosynthesis.

(D) Increasing the rate of degradation of 3-hydroxy-3-methylglutaryl CoA reductase.

12.  Measles, Mumps, Rubella-MMR combined vaccine represents which one of following vaccine categories?

(A) Inactivated/killed

(B) Live, attenuated

(C) Subunit

(D) Toxoid (inactivated toxin)

13.  A haemophiliac man marries a normal woman. They have a daughter who does  not  show  symptoms  of  haemophilia.  If  she  marries  a  haemophiliac  man, what will be the probability of their son displaying symptoms of haemophilia?

(A) 0%

(B) 25%

(C) 50%

(D) 100%

14.  The  conventional  treatment  for  methanol  toxicity  is  to  administer  ethanol. Which of the following explains the basis of this treatment?

(A)  Ethanol acts as a competitive inhibitor to methanol

(B)  Ethanol acts as a non-competitive inhibitor to methanol

(C)  Ethanol destroys the enzymatic activity of alcohol dehydrogenase

(D)  Ethanol blocks the entry of methanol within the cells.

15.  Electrophoresis  of  a  purified  protein  in  SDS-PAGE  in  the  presence  of  2- mercaptoethanol  yields  two  bands  of  35  kDa  and  45  kDa.  However,  in  a  gel  filtration chromatography, the same protein elutes as 80 kDa. What conclusion  will you draw from the results?  

       

          (A) The protein is not purified to homogeneity.  

          (B) Two bands generated in SDS-PAGE due to degradation.  

          (C) The protein is a homodimer   

          (D) The protein is a heterodimer

16.  Lysosomes of a cell were labelled with lysotracker Red. Subsequently, these cells were infected with GFP-transfected Mycobacterium and observed under a fluorescence microscope. What will you observe?

(A)  GFP-Mycobacterium will be colocalized with lysotracker Red labeled lysosomes.

(B)  GFP-Mycobacterium  will  be  separated  from  lysotracker  Red  labeled lysosomes.

(C)  GFP-Mycobacterium will not be detected as they are degraded in the cell.

(D)  Lysotracker   Red   labeled   lysosomes   will   be   degraded   in   GFP- Mycobacterium  infected cells

17.  A  linear  DNA  fragment  which  has  3  restriction  sites  for  BamH1,  is  labeled

/only at the 5  end. This DNA is partially digested with BamH1 in such a way that all kinds of fragments are generated. Under these conditions, how many labeled and unlabeled fragments will be produced?

(A) 3 labeled and 4 unlabeled

(B) 3 labeled and 5 unlabeled

(C) 4 labeled and 5 unlabeled

(D) 4 labeled and 6 unlabeled

18. In the preparation of humanized antibody, part of the antibody molecule is taken from mouse and the remaining is taken from that of human, through genetic engineering technique. Which one of the following statements is true for humanized antibody?

(A) CDRs of mouse IgG is fused with framework regions of human IgG

(B) CDRs of human IgG is fused with framework regions of mouse IgG

(C) CDRs of mouse IgG is fused with CDRs of human IgG

(D) framework regions of mouse IgG is fused with  framework regions of

human IgG

19. A 25-year old man undertakes a prolonged fast for religious reasons. Which  one of the following metabolites will be elevated in his blood plasma after 24  hours?  

       

     (A) Lactic acid  

     (B) Glycogen  

     (C) Ketone bodies  

     (D) Non-esterified fatty acids  

            

20. Which one of the following is not a deficiency disorder?  

       

     (A) Beriberi  

     (B) Night Blindness  

     (C) Poliomyelitis  

     (D) Pernicious Anemia  

Answers:

11. (C) Inhibiting the conversion of 3-hydroxy-3-methylglutaryl-CoA to mevalonate in the pathway for cholesterol biosynthesis.

12. (B) Live, attenuated

13. (C) 50%

14. (A)  Ethanol acts as a competitive inhibitor to methanol

15.  (D) The protein is a heterodimer

16. (A)  GFP-Mycobacterium will be colocalized with lysotracker Red labeled lysosomes.

17. (D) 4 labeled and 6 unlabeled

18. (A) CDRs of mouse IgG is fused with framework regions of human IgG

19. (D) Non-esterified fatty acids  

20.  (C) Poliomyelitis