csir coaching academy

Part I (Multiple choice) Each multiple choice question is designed to have one correct answer.
1. Lipid soluble hormones activate transcription by
a. binding to specific cell-surface receptors
b. phosphorylating a protein kinase
c. binding to a nuclear receptor
d. inhibiting a histone deacetylase
2. Termination of transcription in prokaryotes can be dependent on:
a. intron/exon boundary sequences
b. rho factor
c. the 5'UTR
d. all of the above
3. In E. coli, attenuation and antitermination utilize which structure?
a. stem loop structures in RNA
b. stem loop structures in DNA
c. RNA/DNA hybrids
d. differential protein folding
4. Which of the following cis and trans elements function together in a biological process?
a. Nut and N
b. AAUAAA and CPSF
c. TAR and TAT
d. all of the above

11.2 Processing of Eukaryotic mRNA

5. Histone mRNAs lack:
a. poly A tails
b. introns
c. a 3'UTR
d. all of the above
6. The consensus sequence for poly-A addition is:
a. the site of poly A tail addition
b. AAUAAA
c. downstream of the cleavage site
d. none of the above
7. Which process involves two transesterification reactions?
a. splicing
b. RNA editing
c. capping
d. nuclear transport
8. Splicing joins:
a. two intron sequences
b. two polypeptides
c. two DNA molecules
d. two exon sequences
9. The branch point A residue involved in lariat formation is part of the:
a. intron
b. exon
c. 5'UTR
d. 3'UTR
10. Indicate the order in which the following steps occur in the production of a mature mRNA.
a. initiation of transcription, splicing, addition of 5' cap, addition of poly A tail, transport to cytoplasm
b. initiation of transcription, addition of 5' cap, splicing, addition of poly A tail, transport to cytoplasm
c. initiation of transcription, addition of poly A tail, addition of 5' cap, splicing, transport to cytoplasm
d. initiation of transcription, addition of 5' cap, addition of poly A tail, splicing, transport to cytoplasm
11.3 Regulation of mRNA Processing
11. Sex lethal protein in Drosophila can best be described as a:
a. splicing regulatory factor
b. RNA editing factor
c. transcription factor
d. all of the above
12. Differential splicing of Drosophila slo RNA produces:
a. various Slo proteins with different biological functions
b. various Slo proteins with identical biological functions
c. various slo mRNAs with differential stability
d. various slo mRNAs with new nonsense codons

11.4 Signal-Mediated Transport through Nuclear Pore Complexes

13. The nuclear pore complex allows for:
a. passive diffusion of smaller molecules
b. import of proteins
c. active transport of very large molecules
d. all of the above
14. Which event does not occur within the nucleus?
a. RNA editing in mammals
b. RNA capping
c. polyadenylation
d. RNA editing in protozoans
15. Transport of unspliced HIV mRNA from the nucleus to the cytoplasm of host cells is promoted by a virus-encoded protein named:
a. Tat
b. Rev
c. nucleoplasmin
d. Ran
16. Which type of RNA participates in nuclear export of mRNA?
a. snRNA
b. hnRNA
c. tRNA
d. rRNA

11.5 Other Mechanisms of Post-Transcriptional Control

17. Which of the following does not require protein enzymes?
a. RNA editing
b. excision of group II introns
c. transsplicing
d. excision of group III introns
18. RNA editing is:
a. posttranscriptional alteration of sequences in mRNAs
b. pretranscriptional alteration of sequences in RNAs
c. posttranscriptional joining of two RNA molecules
d. none of the above
19. Which of the following can affect the cytoplasmic location of mRNAs?
a. the cytoskeleton
b. cytochalain B
c. polyribosomes
d. all of the above
20. All of the following statements about replication origins are true except:
a. A bacterial chromosome has one origin of replication
b. A eukaryotic chromosome has one origin of replication
c. Replication origins are unique DNA segments that contain multiple short repeated sequences
d. Replication origins usually contain an AT-rich stretch
21. What experimental technique was utilized to show that DNA replicated by a semiconservative process?
a. density gradient equilibrium centrifugation
b. fiber autoradiography
c. electron microscopy
d. gel electrophoresis
22. In E. coli, the role of DnaB in DNA replication is to
a. bind single stranded DNA to prevent reannealing of the duplex
b. unwind the DNA duplex
c. ligate adjacent Okazaki fragments
d. correct errors introduced by DNA polymerase
23. Which of the following activities is not needed for replication of the E. coli chromosome?
a. telomerase
b. ligase
c. primase
d. polymerase
24. All of the following statements about Type I topoisomerase (Topo I) are true except:
a. Topo I removes DNA supercoils in an ATP-dependent reaction
b. Topo I from eukaryotic cells can remove both positive and negative supercoils
c. Topo I from E. coli can remove only negative supercoils
d. Topo I is essential for viability in E. coli
25. The mutation rate in bacterial cells is
a. one mistake in one thousand nucleotide polymerization events
b. one mistake in one million nucleotide polymerization events
c. one mistake in one billion nucleotide polymerization events
d. one mistake in one trillion nucleotide polymerization events