Questions of the Week


Note: Questions of the week are given at the end of labs 1, 3, 5, 6, 7, 9, 10, 12, 13, 14 


  • Question of the Week No. 1: Mitosis
  • Answer:   Colchicine arrests mitosis at the metaphase stage, because by inhibiting microtubule polymerization, chromosomes cannot move to opposite poles; therefore the anaphase stage won't be formed.
  • Additional information:   Colchicine is used to produce polyploidy; this is because without polymerization of microtubules replicated chromosomes at the metaphase stage cannot separate at anaphase and do not migrate to the opposite poles. 



  • Question of the Week No. 2: Restriction Mapping
  • Answer:    
  • a)
  • 5'  CTCGAC 3'                                                                                                

                 3' GAGCTG 5'

  •  5' GTCGAG 3'

                 3' CAGCTC 5'


  •      No; because the newly-generated sequences are not palindromic, therefore they won't be recognized by

                      either enzyme.


  • Question of the Week No. 3:  Polymerase Chain Reaction
  • Answer:
  •       1.  The set of primers shown in (a) is correct.
  •       2.  Forward 5' TTGTAT 3'            Reverse 5' GATCTA 3' 

                 3. The reverse primer binds to the 3' end of the target sequence on the upper strand.

                           The forward primer binds to the 3' end of the target sequence on the lower strand.


              Question of the Week No. 4: Cloning 1

  • Answer: 
  • a) Tetracycline; because the AmpR gene has been disrupted by the PstI cut; this will interrupt the synthesis of the ampicillin-resistance protein.


  • b) The E. coli cells contain non-recombinant plasmids. 



  • Question of the week No. 5: Cloning 2
  • Answer:   
  • All kanamycin-resistant transformants will die on ampicillin-rich medium.  The reason is that the EcoRI-HindIII fragment cloned into the vector will disrupt the structure of the ampicillin-resistance gene.                           


  •  Question of the Week No. 6: Southern Blotting 2
  • Answer:   QOTW6.PDFQOTW6.PDF                



  •  Question of the Week No. 7: Regulation of Gene Expression
  • Answer: 
  • Type 2.
  • The reporter protein is translationally fused with the protein of interest; i.e. the reporter protein will be detected in areas where the protein of the gene of interest is expressed. 




  • Question of the Week No. 8:  Crossing Over
  • Answer:  
  • Parental                                                                       OOOOOOOO  or  OOOOOOOO
  • Meiotic segregation without crossing over         OOOOOOOO  or  OOOOOOOO
  • Meiotic segregation with crossing over               OOOOOOOO  or  OOOOOOOO  or
  •                                                                                      OOOOOOOO  or  OOOOOOOO
  • Aberrants                                                                   OOOOOOOO or the like arrangements                




  • Question of the Week No. 9:  Complementation Test
  • Answer:              

                  QOTW 9.PDFQOTW 9.PDF                                                                    


  •   Question of the Week No. 10:  SSLP Mapping
  • Answer: