MolBioExam4

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  1. Does bacteria use polyadenylation to increase the stability of a transcript?
    NO! eukaryotes does!
  2. Which domains typically possess transposons in their genomes?
    bacteria and eukaryotes
  3. Does both bacteria and eukaryotes exhibit occasional / wide-spread splicing of RNAs ?
    YES!
  4. Bacterias have spliceosomes. True/False
    FALSE. euks do!
  5. Which domain posttranscriptionally process tRNAs and RNAs?
    eukaryotes and bacteria
  6. Which domain typically possesses retrotransoposons in their genomes?
    eukaryotes
  7. Eukaryotes have polysomes.
    ex: multiple ribosomes simultaneously bound to a typical mRNA.
    TRUE/FALSE?
    TRUE
  8. Bacteria have polysomes. 
    ex: Multiple ribosomes simultaneously bound to a typical mRNA.
    TRUE/FALSE?
    TRUE
  9. Do eukaryotes have coupled transcription and translation in which translation of a transcript begins before transcription is completed?
    NO!-bacteria has coupled transcription and translation
  10. Which domain have promoters that include sequences that are downstream relative to transcription start site (ex: notated w/#s > +!) ?
    eukaryotes! 
  11. Which of the following is FALSE about transposons?
    A. They are synonymous w/ transposable elements.
    B. They always encode reverse transcriptase.
    C. They make up a large fraction, sometimes half/more, of the seq of euk genomes.
    D. When active, they typically encode the transposase and other genes needed for movement,
    E. They're the likely origin of aspects of the adaptive immune system of vertebrates.
    B. They always encode reverse transcriptase.
  12. Which of the following is FALSE about transposons ?
    A. Inversion
    B. Deletion
    C. Insertion
    D. Translocation
    E. All of the above can occur
    D. Translocation 
  13. Which of the following is used by retrotransposons?
    A. Cut-and-paste transposition
    B. Replicative transposition
    C. Bacterial Transduction
    D. Transposition via an RNA intermediate 
    E. Site-specific insertion
    D. Transposition via an RNA intermediate 
  14. Which of the following is FALSE of RNA synthesis by RNA polymerase?
    A. RNA synthesis is less processive during elongation than during initiation.
    B. Synthesis begins w/ pol binding 2 rNTP molecules. 
    C. The pol frequently releases the nascent transcript before it reaches 8-10 nucs in length.
    D. The addition of an rNTP to a growing transcript is a magnesium ion-dependent reaction.
    A. RNA synthesis is less processive during elongation than during initiation.
  15. Which of the following characteristics of DNA-dependent DNA synthesis (ex: DNA replication) is NOT the same for DNA-dependent RNA synthesis (ex: transcription)?
    A. Synthesis requires a template.
    B. Initiation involves recognition of a specfic DNA seq.
    C. Initiation of synthesis requires a primer.
    D. Synthesis is catalyzed in the 5'-3' direction.
    C. Initiation of synthesis requires a primer.
  16. Below is the template strand of a DNA w/ the transcriptional start site (TSS) highlighted. 

    5'-TTACTATCCGGCTAACTAGTC-3'

    Which is the correct first 4 nucs of an RNA transcribed 4rm this template?
    A. 5'-UUGA
    B. 5'-AACU
    C. 5'-TTGA
    D. 5'-TAGC
    E. 5'-AGCC
    F. 5'-UAGC
    F. 5'-UAGC
  17. Which of the following euk RNA pol is responsible for transcribing nearly all protein-coding genes?
    A. RNA Pol I
    B. RNA Pol II
    C. RNA Pol III
    D. RNA Pol IV
    B. RNA Pol II
  18. Which of the following statements about promoter consensus seq in E.coli is TRUE? (>1 answer)
    A. All promoter seq in cell are the same as the consensus.
    B. Each sigma factor recognizes a diff consensus seq. 
    C. The consensus represents least common nuc and spacing in promoters.
    D. The core promoter seq can sometimes be found hundreds of nucs up/down stream of the TSS (transcriptional start site).
    B. Each sigma factor recognizes a diff consensus seq. 
  19. Which of the following is FALSE with respect to assembly of the components necessary for initiation of transcription in a euk?
    A. TATA binding protein binds to all core promoters, even tho many lack TATA seq motif.
    B. All core euk promoters bind to the same factors.
    C. TFIIB, TFIID, TFIIF and TFIIH bind to promoters of mRNA transcripts to recruit RNA Pol II and lead to transcription initation.
    D. Mediator bridges transcriptional activators and RNA pol II.
    B. All core euk promoters bind to the same factors.
  20. Which of the following statements about the spliceosome is FALSE?
    A. recognizes specific seq in mRNA.
    B. made up of RNA and protein.
    C. provides the only mech for performing RNA splicing in cells. 
    D. found in euks.
    C. provides the only mech for performing RNA splicing in cells. 
  21. The nucleophile of the first step of spliceosome-mediated pre-mRNA splicing is the 
    A. 2' hydroxyl of the branch point adenosine.
    B. 3' hydroxyl of branch point adenosine.
    C. 3' hydroxyl of 5'splice site exon.
    D. 2' hydroxyl of 3'splice site intron.
    A. 2' hydroxyl of the branch point adenosine
  22. Which of the following is NOT correct of RNA processing rxns? 
    A. Splicing can alter seq of protein that results 4rm a transcript.
    B. 5' capping increases stability of a transcript.
    C. Degradation rate of a transcript is diff for diff transcripts. 
    D. Poly adenylation is cued by a seq in the transcript. 
    E. Posttranscriptional modifications to mRNA bases cannot effect function of the encoded proteins.
    E. Posttranscriptional modifications to mRNA bases cannot effect function of the encoded proteins. 
  23. Which of the following experimental results provides evidence that the genetic code is read in triplets? 
    A. When 2 insertion mutations are combined, the 1st mutation causes a frameshift which is not restored by 2nd mutation. 
    B. Combining 3 insertion mutations often results in an active protein seq.
    C. A single deletion mutation results in inactivation of the gene, even when mutation occurs in a region of the gene that can allow single nuc substitutions. 
    D. When an insertion mutation is combined w/ a deletion mutation, the 1st mutation causes a frameshift, but the 2nd mutation restores wild-type reading frame.
    B. Combining 3 insertion mutations often results in an active protein seq.
  24. What 2 processes are likely to STABILIZE a particular msgr RNA increasing its half=life in vivo?
    5'Cap Formation & PolyA-Tail Formation
  25. Splicing, Alternative splicing, RNA Editing(Base Modification / Indel Formation), and Actiity of a self-splicing intron are ALL examples of what?
    examples that have the potential to alter the CODING seq of a RNA relative to the unprocessed transcript.
  26. Which of the following statements is most accurate w/ respect to the steady-state amt of an mRNA transcript detected w/in a cell? 
    A. Unequal rates of degradation by exosome determine amt of each transcript in a cell.
    B. All transcripts have an equal rate of degradation, so only the rate of transcription determines amt of transcript present.
    C. amt of a transcript is determined by binding of TATA box binding protein to promoter.
    D. amt of transcript is a result of its rate of transcription and rate of degradation.
    E. coupling of DNA replication w/ transcription determines amt of a transcript present.
    D. amt of transcript is a result of its rate of transcription and rate of degradation.
  27. The genetic code is degenerate because...
    A. 1 particular AA can only be encoded by 1 codon.
    B. not all possible codons are used to code for AAs.
    C. 1 particular AA can be encoded by +1 than 1 codon. 
    D. 1 particular codon can code for +1 AA
    C. 1 particular AA can be encoded by +1 than 1 codon. 
Author:
mnvang321
ID:
313237
Card Set:
MolBioExam4
Updated:
2015-12-14 22:51:17
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molbio
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MolBioExams
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Exam 4
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