Genetics First Quiz

35 Questions | Total Attempts: 77

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Genetics Quizzes & Trivia

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Questions and Answers
  • 1. 
    Which of the following is incorrect about DNA?
    • A. 

      The van der waals is greatest at 0.3-0.4 nm

    • B. 

      The two antiparallel streands are left handed helix

    • C. 

      .drugs can contact with bases through Dna grooves

    • D. 

      Sugar and phosphate forms the back bone of strands

  • 2. 
    Most of the cellular function depends on
    • A. 

      Dna

    • B. 

      Fatty acids

    • C. 

      Proteins

    • D. 

      Glucose

  • 3. 
    Melting tempreture denaturates.... Of Dna helical shape
    • A. 

      60%

    • B. 

      80%

    • C. 

      24%

    • D. 

      50%

  • 4. 
    If the sequence of DNA coding strand was 5’/ TAACG/3’ , so the sequance of new transcript RNA is :
    • A. 

      5’ TAACG 3’

    • B. 

      5’ UAACG 3’

    • C. 

      5’ AUUGC 3’

    • D. 

      non of the above

  • 5. 
    The subunit that responsible for formation of phosphodiester bond :
    • A. 

      Alpha

    • B. 

      Beta’

    • C. 

      Beta

    • D. 

      Delta

  • 6. 
    All of the following rearding polymerases are true Except: 
    • A. 

      Rna pol doesn’t require a primer

    • B. 

      Rna pol has no proofreading activity

    • C. 

      DNA pol has no proofreading activity

    • D. 

      Rna pol will synthesize Rna from 5’ to 3’ direction

    • E. 

      Two of the above

  • 7. 
    All of the following is true about RNA EXCEPT : 
    • A. 

      The 60S ribosomal subunit consists of about 50 polypeptide combined with (5S,5.8S,18S rRNA)

    • B. 

      Every three nitrogenous base in mRNA form one codon specific for one amino acid

    • C. 

      At the 3’ end in mRNA there is a poly A tail

    • D. 

      Each tRNA consist of 70-90 nucleotide

    • E. 

      E. Loop III in tRNA termed the variable loop

  • 8. 
    RNA primer formed during DNA synthesis is removed by : 
    • A. 

      Primase

    • B. 

      DNA Polymerase I

    • C. 

      DNA Polymerase II

    • D. 

      RNA Polymerase I

    • E. 

      E. DNA Polymerase III

  • 9. 
    The nucleotide involved in DNA synthesis is : 
    • A. 

      Ribonucloside triphosphate

    • B. 

      Deoxyribonucloside triphosphate

    • C. 

      Ribonucloside monophosphate

    • D. 

      Deoxyibonucloside monophosphate

    • E. 

      Deoxyribonucloside diphosphate

  • 10. 
     A eukaryotic cell lacking telomerase would :    
    • A. 

      Be unable to take up DNA from solution

    • B. 

      Be unable to identify where transcription should begin

    • C. 

      C. Have a greater potential to become cancerous

    • D. 

      D. Incorporate one extraneous nucleotide for each Okazaki fragment

    • E. 

      E. Experience a gradual reduction in length with each replication cycle

  • 11. 
     RNA primer considered essential during DNA synthesis by DNA Polymerase III , that’s regarded to :    
    • A. 

      The enzyme requires a free 5’-OH group

    • B. 

      The enzyme requires a free 5’-PO4 group

    • C. 

      The enzyme requires a free 3’-OH group

    • D. 

      No particular reason ; that is simply the observation

    • E. 

      The RNA polymerase III synthesizes DNA only from 5’ to 3’ prime

  • 12. 
    In mismatch repair mechanism , the endonuclease activity which cut the nascent DNA strand is done by:
    • A. 

      MutH

    • B. 

      MutL

    • C. 

      MutS

    • D. 

      MutD

    • E. 

      UvrD

  • 13. 
    In nucleotide excision repair machinery , which of the following protein processes the helicase activity ? 
    • A. 

      UvrA

    • B. 

      UvrB

    • C. 

      UvrC

    • D. 

      UvrD

    • E. 

      Excinuclease UvrABC

  • 14. 
     Xeroderma pigmentosum in human is associated with a mutation in 
    • A. 

      Photoreactivation

    • B. 

      Nucleotide excision repair

    • C. 

      Base excision repair

    • D. 

      Mismatch repair

    • E. 

      Double strand break repair

  • 15. 
    Regarding eukaryotic TATA box which is not true:
    • A. 

      Its nucleotides are TATAAA

    • B. 

      -35 nucleotides upstream from start site

    • C. 

      Recognized by TF II

    • D. 

      Determines where translation starts

    • E. 

      None of the above

  • 16. 
    Inducible genes express their protein products only in the presence of an inducer:
    • A. 

      True

    • B. 

      False

  • 17. 
    RNAP III synthesizes/ catalyzes
    • A. 

      Most snurps

    • B. 

      45S rRNa

    • C. 

      5s rRNA

    • D. 

      MRNA

    • E. 

      All of the above

  • 18. 
    Which of the following TF II contains the Tata binding protein:
    • A. 

      E

    • B. 

      A

    • C. 

      B

    • D. 

      G

    • E. 

      D

  • 19. 
    TF II ______ brings the RNAP II to the promoter site while the TFII _____ activates it by phosphorylation using a _____ : 
    • A. 

      F, H, kinase

    • B. 

      F, E, ATP

    • C. 

      E, H, kinase

    • D. 

      D) D, E, kinase

    • E. 

      E) none of the above

  • 20. 
    Regarding RNA transcript:
    • A. 

      Has introns and exons

    • B. 

      RNA molecules produced by RNAP II

    • C. 

      Immature

    • D. 

      Needs processing

    • E. 

      All of the above is correct

  • 21. 
    Which of the following is not associated with the importance of mRNA capping? 
    • A. 

      Protects 5' end from exonuclease

    • B. 

      stabilizes mRNA

    • C. 

      helps in recognition by ribosome

    • D. 

      increases efficiency of translation

    • E. 

      Aids in transport of mRNA to the cytoplasm

  • 22. 
    One of these rRNA isn't released from the precursor pre-rRNA
    • A. 

      18S

    • B. 

      5.8S

    • C. 

      28S

    • D. 

      5S

  • 23. 
    Regarding addition of poly (A) tail, which of the following is true? 
    • A. 

      100-200 A bases

    • B. 

      post transcription modification

    • C. 

      added after AAUAAA by 15-20

    • D. 

      uses ATP

    • E. 

      all of the above

  • 24. 
    Splicing of exons and removing of introns is bought about by: 
    • A. 

      small nuclear RNA

    • B. 

      RNA polymerase 1

    • C. 

      ATPase activity

    • D. 

      Snurps

    • E. 

      None of the above

  • 25. 
    In which of the following diseases does the body produce ab against snurps? 
    • A. 

      xeroderma pigmentosum

    • B. 

      SLP

    • C. 

      HNPCC

    • D. 

      bloom disease

    • E. 

      none of the above

  • 26. 
    All the following modifications took place on the pre tRNA molecules , Except :
    • A. 

      Addition of the sequence of CCA at the 5' end

    • B. 

      Excision of introns present in the anticodon loop

    • C. 

      .methylation of uracil into thymine

    • D. 

      None of the above

  • 27. 
    Methotrexate can develop resistance by :
    • A. 

      Gene diminution mechanism

    • B. 

      Gene rearrangment and recombination mechanism

    • C. 

      Gene amplification mechanism

    • D. 

      None of the above

  • 28. 
    Permease enzyme is encoded by
    • A. 

      Lac z gene

    • B. 

      Lac Y gene

    • C. 

      Lac A gene

    • D. 

      None of the above

  • 29. 
    Ll the followings are true about constitutive genes ,Except
    • A. 

      They are negatively regulated by repressors

    • B. 

      Known as housekeeping genes

    • C. 

      They are expressed at a low rate

    • D. 

      Required for basic cellular functions

  • 30. 
    It transcribes tRNA and 5S rRNA and some nuclear RNAs (snRNA ) :
    • A. 

      Rna polymerase I

    • B. 

      Rna polymerase III

    • C. 

      Rna polymerase II

    • D. 

      Mitochondrial rna

  • 31. 
    In the transcriptional regulation involving chromatin which of the following is methylated
    • A. 

      Adenine

    • B. 

      Cytosine

    • C. 

      Guanine

    • D. 

      Thymine

  • 32. 
    Which one of these codons is the starting codon
    • A. 

      AGA

    • B. 

      AUG

    • C. 

      AGU

    • D. 

      None of the above

  • 33. 
    Which of the following regarding characteristics of genetic code is not true
    • A. 

      Some codons have the ability to code for more than one amino acids

    • B. 

      All organisms share the same genetic code

    • C. 

      Only methionine and tryptophan are coded for by one codon each

    • D. 

      The first base of the anticodon follows less rigid requirements when it binds to its opposing last base of codon than the last two bases of the anticodon

  • 34. 
    CAAT box/GC box are members of regulated expression elements
    • A. 

      True

    • B. 

      False

  • 35. 
    Which of the following is not involved in post transcriptional regulation
    • A. 

      Alternative splicing

    • B. 

      Regulation of RNA stability

    • C. 

      MRNA editing

    • D. 

      None of the above