37. What method can be used to functionally inactivate a gene without altering its sequence?

1. gene knockout 　

2. RNA interference 　

3. dominant negative mutation 　

4. CRISPR/Cas9 system
(A) 1 and 2 are correct.
(B) 2 and 3 are correct.
(C) 2 and 4 are correct.
(D) 1, 2 and 4 are correct.
(E) All of above are correct.

33. Predict the consequences of a temperature sensitive mutation in which the phosphorylation of the b-catenin protein is blocked. Above the permissive temperature, (A) b-catenin levels will increase and b-catenin will be constitutively active. (B) b-catenin levels will increase and b-catenin will be inactive. (C) b-catenin levels will decrease and cells will be inactive. (D) b-catenin will remain decrease and cells will be more sensitive to Wnt signaling (E) b-catenin will remain constant but cells will be unresponsive to Wnt signaling.

34. Fully differentiated mouse fibroblasts can be reprogrammed or induced to form pluripotent stem cells when transfected with retroviral vectors expressing: 　 1. KLF4.2. c-MYC. 3. SOX2. 4. Ngn1 5. Oct4 (A) 1, 2, 3, 5 (B)1, 2, 3, 4 (C) 1, 2, 4, 5 (D) 1, 3, 4, 5 (Ε) 2, 3, 4, 5

35. Which one is NOT the marker of Epithelial-mesenchymal transition? (A) N-cadherin (B) E-cadherin (C) vitronectin (D) integrin (E) Zebl

36. Which statement listed below concerning general molecular biology techniques is correct? 1. Run-on transcription determines the translational rate. 　 2. Primer extension determines the start of transcription. 　 3. Southern blot determines if a probe is complementary to a DNA target. 　 4. Northern blot determines the size and abundance of a RNA. 　 5. Gel mobility shift assay determines whether a protein binds DNA. (A) 1, 2, 3, 4 are correct. (B) 1, 3, 4, 5 are correct. (C) 2, 3, 4, 5 are correct. (D) 1, 3, 4, 5 are correct. (E) All of above are correct.

38. Next generation sequencing is much more efficient than the Sanger method because: 　 1. It uses an RNA template instead of DNA. 　 2. It uses gel electrophoresis to resolve end-labeled strands of DNA. 　 3. It uses PCR amplification. (A)1 is correct (B) 2 is corrrect (C) 3 is correct (D) 1 and 3 are correct (E) All of above are correct

39. Compare the advantages and limitations of microarrays and Northern blots for analyzing gene expression. Which statement listed below is correct? 　 1. Microarrays allow a more global analysis of gene expression by analyzing thousands 　 2. Microarrays data analysis can reveal groups of known and unknown genes that are regulated in a coordinated fashion. 　 3. Northern blots allow the analysis of only a few genes at a time. 　 4. Northern blot can reveal the presence of multiple mRNAs from one gene locus that may be differentially expressed. The presence of multiple mRNAs could be missed by microarray analysis. (A) 1, 2, 3 are correct. (B) 1, 3, 4 are correct. (C) 2, 3, 4 are correct. (D) 1, 2, 4 are correct. (E) All of above are correct.

40. Which of the following best describes the function of reverse transcriptase? (A) It's involved in viral attachment to a host cell. (B) It uses an RNA template to make a double-stranded DNA. (C) It uses DNA to synthesize an RNA in the 3' to 5' direction. (D) It joins the gene segments that code for antibodies. (E) Its reaction products can be inserted directly into plasmid.

1. Which of the following pairs of bonds can rotate within a peptide backbone and the torsion angle of the latter is assigned as psi angle? (A)(B)(C)(D)(E)

2. Which of the following statements is   false  ? (A) One protein has one conformation but has many configurations. (B) An α-helix can be destabilized by the presence of two Lys residues near the amino terminus of the α-helix. (C) Determining the precise spacing of atoms within a large protein is possible only through the use of x-ray diffraction. (D) Protein domains may retain their correct shape even when separated from the rest of the protein. (E) Proteins are classified within families or superfamilies based on similarities in structure and/or function.

3. RecA enzyme requires for catalysis. When the enzyme lacks , it would be referred to as the: (A) apoenzyme. (B) substrate. (C) coenzyme. (D) holoenzyme. (E) prosthetic group.