Download SC/BIOL 3130 Midterm 1 July 20, 2015 This exam consists of 35

SC/BIOL 3130 Midterm 1
July 20, 2015
This exam consists of 35 multiple-choice questions. Answer
using the scantron sheet provided.
The time of this exam is 75 minutes
Good luck!
1. A new insulin gene was isolated and a study was planned to look at the function of the promoter
region. Which of the following would be the best choice for this study?
A.
B.
C.
D.
E.
F.
southern analysis immunoblotting reporter gene assay
PCR Immunoprecipitation
None of the choices are correct. 2. Which of the following chemicals would be the most appropriate for the 5’ labeling of a DNA
strand with a radioactive phosphate?
A. α-32P-ATP
B. 35S -Methionine
C. β-32P-ATP
D. γ-32P-ATP
E. 14C
F. None of the choices are correct. 3. It is suspected that a novel protein only interacts with the promoter region of a gene. Which of the
following techniques should be used to confirm this suspicion?
A. EMSA
B. DNase footprinting C. Filter binding D. Gel mobility shift assay E. All of the choices are correct.
F. None of the choices are correct.
4. An experiment was designed to obtain nonspecific transcription from both strands of a DNA
molecule. Which of the following strategies would be most effective in achieving this?
A. Include the RNA holoenzyme in the reaction. B. Use the core enzyme of RNA polymerase. C. Enrich the preparation with sigma subunit. D. Use intact DNA. E. Include the RNA holoenzyme in the reaction and use the core enzyme of RNA polymerase are both
effective.
6. Dimethyl sulfate is used to A.
B.
C.
D.
E.
cleave DNA molecules. denature or melt DNA promote region. remove methyl groups from RNA. add methyl groups to DNA.
promote the binding of RNA polymerase to DNA.
7. Which of the following statement is false regarding the sigma-factor? A.
B.
C.
D.
E.
It does not have a DNA-binding domain. Interaction with the core enzyme unmasks the DNA-binding region. Subregions 2.4 and 4.4 are involved in promoter recognition. It can also bind to the nontemplate strand. It can bind to the -10 box.
8. Which of the following would most likely occur if an in vitro transcription assay is performed using
a cell extract containing an alpha subunit without the C-terminal domain? A.
B.
C.
D.
E.
Polymerase would become tightly associated with the promoter. Polymerase would become more susceptible to proteolysis. Transcription will be accelerated. Polymerase complex would be loosely associated with the promoter. Recognition of the UP element would be faster.
9. Which of the following is most involved in elongation of the RNA transcript?
A.
B.
C.
D.
E.
sigma factor
UP elements -10 region both sigma factor and UP elements
none of these choices are correct
10. Which of the following does not have a DNA-binding domain? A.
B.
C.
D.
E.
F.
sigma-factor
CAP alpha-factor beta beta prime
none of the choices are correct
11. Which of the following statements is true about a lac operon with the following genotype? I- Oc Z+ Y-
I- O+ Z- Y- A. A repressor protein will be constitutively produced. B. β-galactosidase will be constitutively produced. C. A cis-dominant mutation is present. D. Permease will be constitutively produced. E. Both A. a repressor protein will be constitutively produced and C. a cis-dominant mutation is
present are correct.
12. Which of the following plasmids could be used to restore inducible regulation of -galatosidase in
+
c
- + +
this mutant: I O Z Y A ? A.
B.
C.
D.
E.
I+ Oc Z- Y+ A+ I+ Oc Z- Y- A- I- O+ Z+ Y+ A+ I-Oc Z+ Y+ A+ Both A. I+ Oc Z- Y+ A+ and B. I+ Oc Z- Y- A- are correct.
13. Which of the following statements is true about a lac operon with this genotype?
I-d O+ Z+ Y- AA.
B.
C.
D.
E.
The operon is repressible. The operon is nonrepressible. The mutation is cis-dominant. The operon is uninducible.
None of the choices are true.
14. Which of the following is most likely to occur if the level of glucose is low in a bacterial cell?
A. Cyclic-AMP levels will be depressed.
B. CAP will assist in stimulating transcription of the lac operon. C. β-galactosidase activity will be inhibited. D. Both Cyclic-AMP levels will be depressed and β-galactosidase activity will be inhibited are
correct. E. None of the choices are correct.
15. Which of the following is true about the action of CAP at the lac promoter? A. CAP binds directly to the promoter stimulating polymerase to bind. B. CAP-AMP blocks recruitment of polymerase to the promoter. C. CAP binds to the CTD of Sigma. D. Binding of the CAP-cAMP to the lac activator-binding site recruits RNA polymerase. E. CAP monomer binds directly to the promoter stimulating polymerase to bind and CAP binds the
CTD of Sigma are both correct.
F. None of the choices are correct.
16. Which of the following is true about the regulation of the trp operon? A.
B.
C.
D.
E.
F.
An aporepressor is involved.
A corepressor is involved. Attenuation is one of the mechanism of control. Negative control is involved. All of the choices are true.
None of the choices are true.
17. In the process of creating a trp operon mutant, the UGG codons within the leader sequence were
accidentally deleted. Which of the following would be a likely observation in the transcription assays? A.
B.
C.
D.
E.
F.
RNA polymerase cannot bind to the promoter. The operon is permanently inhibited. Attenuation would be impaired. Termination would be triggered. No tryptophan would be made.
No leader peptide would be made.
18. Which of the following sigma specificity factors is involved in middle gene transcription during
SPO1 phage infection of bacteria? A.
B.
C.
D.
E.
gp33
gp28 gp34
gp43 host sigma
19. Predict the outcome of the removal of the N gene from the DNA sequence of the lambda phage: A. lysogenic cycle will be induced. B. entry into the bacterial host will be blocked.
C. antitermination will be affected. D. transcription from the left promoter will be interrupted. E. antitermination will be affected and transcription from the left promoter will be interrupted are
correct.
F. None of the choices are correct.
20. Which of the following is involved in maintaining lysogeny in lambda phage? A.
B.
C.
D.
E.
PRE PRM PRL PRO all of the choices are correct.
21. Which of the following statements is true about the cro gene? A.
B.
C.
D.
E.
It must be stimulated during lysogeny. Its product promotes repressor activity. cro repression is important to lysogeny. It is adjacent to the Q gene. It must be stimulated during lysogeny and its product promotes repressor activity are correct.
22. Which of the following operators is a target of cI gene production? A.
B.
C.
D.
E.
F.
OR1 OR2 OL1 OL2 all of the choices are correct.
none of the choices are correct.
23. Which of the following are products of RNA polymerase II activity?
A. tRNA B. microRNA C. hnRNA D. tRNA and microRNA E. both B. microRNA and C. hnRNA
24. An antibody was produced and used in an immunohistochemical assay to detect the location of
RNA polymerase II in a thin section of a liver biopsy. The section was stained with the antibody that
had been labeled with a fluorescent tag, and then viewed under a fluorescent microscope. State where
you would expect to find positive staining if the enzyme is present.
A.
B.
C.
D.
E.
rough endoplasmic reticulum nucleoplasm nucleolus endoplasmic reticulum ribosomes
25. One effect of the deletion of the hRPB1 subunit of RNA polymerase II is A.
B.
C.
D.
E.
loss of the oligosaccharide-binding domain. inability of polymerase to bind to transcriptional activators. slowed elongation rate. non-viable cells. extended CTD.
26. Which of the following is the correct order of addition of general transcription factors to the
initiation complex? A.
B.
C.
D.
E.
TFIIA+TFIID, TFIIE, TFIIIIB, TFIIF + pol II, TFIIH TFIIA+TFIID, TFIIB, TFIIH, TFIIF + pol II, TFIIE
TFIIA+TFIID, TFIIB, TFIIF + pol II, TFIIE, TFIIH TFIIA+TFIID, TFIIH, TFIIIIB, TFIIF + pol II, TFIIE TFIIF + pol II, TFIIA+TFIID, TFIIH, TFIIIIB, TFIIE
27. Which of the following is considered a universal transcription factor? A.
B.
C.
D.
E.
TFIIA TFIIB TFIID TFIIF TFIIH
28. Which of the following would you choose to study the role of polymerase subunits in elongation? A.
B.
C.
D.
E.
epitope tagging immunoprecipitation in vitro transcription western blotting DNAase footprinting
29. An experiment is planned to study the effect of reducing the transcription of the myosin gene.
Which of the following inhibitors would be useful in this study? A.
B.
C.
D.
E.
alpha-amanitin DMS heparin
ammonium sulfate none of the choices are correct.
30. Phosphorylation of RNA Pol II results in the formation
A. IIa
B. IIo
C. IIc
D. IIIo
E. None of the choices are correct
31. The TATA box binding protein (TBP) requires the TATA box to introduce a bend in DNA
A. True
B. False
32. At least eight TAFs are associated with TFIID
A. True
B. False 33. TAFs are universally required for the transcription of Class II genes A. True B. False 34. Enhancers and repressors can be tissue-specific based on the types of DNA-binding proteins that
are present in the cell.
A. True
B. False
35. Transcriptional changes that occur when organisms respond to environmental changes are in part
due to changes in RNA polymerase.
A. True
B. False