104年 - [非官方正解]104 國立中央大學_碩士班考試入學試題_生命科學系分子與細胞生物組(一般生、在職生) ：分子生物學#126358

1. The 5' -CAP of an mRNA is formed by______.
(A) 7-methyl guanine (B) 5-methyl adenine (C) 2-acetyl cytosine (D) 7-methyl uridine

2. Agrobacterium cells carrying ______inserted with interested gene can infect plant cells and express the interested gene in the target cells.
(A) T7 plasmid (B) phage DNA (C) PCDNA3 vectors (D) T-DNA plasmids

3. The short DNA fragments found in the lagging strand of a replicating DNA are called as______ fragments.
(A) Yamanaka (B) Okazaki (C) Thomas (D) Obokata

4. The enzyme ______synthesizes multiple repeated sequences at the ends of linear chromosomes to protect them from replicative senescence.
(A) telomerase (B) DNA polymerase (C) RNA polymerase (D) DNA primase

5. The enzyme ______promotes eukaryotic homologous recombination.
(A) RecA (B) CRE recombinase (C) Flippase (D) Rad51

6. The______ transposon is an example of DNA-only transponson.
(A) P-element (B) L1 (C) Tyl (D) Alu

7. The________ method/assay can be used to identify DNA sequences bound by transcription factors to the resolution of each base.
(A) EMSA (B) ChIP (C) Footprinting (D) RT-PCR

8. Single strand circular progeny DNAs can be produced by________ mode of DNA replication. (A)θ(B) bidirectional (C) rolling circle (D)λ

9. The separation of double strand DNA during replication is triggered by________.
(A) helicase (B) primase (C) topoisomerase (D) DNA polymerase δ

10. The most common DNA damage caused by UV radiation is creation of______.
(A) truncation (B) deletion (C) purine dimers (D) pyrimidine dimers

11. RuvC functions to______ during prokaryotic homologous recombination (A) synthesize DNA (B) create heteroduplex (C) push branch migration (D) resolve holiday junction

12. To avoid being recognized as broken ends, the ends of linear chromosomes______.
(A) form T-loops (B) become blunt ends
(C) form chromosome conjugates (D) are bound by DNA plolymerase

13. The factor PCNA functions as a______ during DNA replication.
(A) DNA polymerase (B) primase (C) Heliase (D) sliding clamp

14. Double strand breaks (DSB) of DNA at G0 phase are most likely repaired by______.
(A) nonhomologous end-joining (B) Strand-directed repair (C) Mismatch repair (D) Bas excision repair

15. Continued from question 14, what will happen if DSB happens during S phase?
(A) nonhomologous end-joining (B) Nucleotide excision repair
(C) Mismatch repair (D) Homologous recombination

16. Mutations happened at the __________will result in RFLP.
(A) promoter (B) enhancer (C) terminator (D) restriction site

17. The insertion and excision of a Tn3 transposon will leave a__________in the target DNA.
(A) direct repeat (B) inverted repeat (C) restriction site (D) stop codon

18. The ends of a retrovirus genome are arranged as__________.
(A) direct repeats (B) LTRs of inverted sequence (C) directly repeated LTRs (D) short inverted repeats

19. Nucleosomes are__________.
(A) found in all organisms (B) formed by DNA and histones
(C) assembled only during transcription (D) the places where ribosome assembled

20. Deamination of cytosine will generate a__________ base.
(A) G (B) A (C) T (D) U

21. A variation that does not involve a change in DNA sequence but can be passed from one generation to another is a(n)__________.
(A) enhancer trap (B) replication origin (C) epigenetic condition (D) mutant chromosome

22. All of the following are associated with the formation of a functional miRNA except
(A) lack of an open reading frame (ORF). (B) 5' GTP cap and 3' poly A tail.
(C) stem-loop structures. (D) translation on ribosomes.

23. Mutations introduced into reporter constructs are used to study
(A) the DNA sequences that are important for regulating gene expression levels.
(B) the effects on cell function of expression of heterologous proteins.
(C) colorimetric assays.
(D) protein protein interactions.

24. A cis-acting DNA sequence that modulates the basal rate of transcription of a gene is termed a(n)_______.
(A) initiator (B) activator (C) promoter (D) enhancer

25. Zinc-finger peptide motifs are responsible for what aspect of protein function?
(A) kinase activity (B) DNA binding (C) mRNA splicing (D) methylation

26. How are complex processes such as sporulation, synthesis of flagella, and nitrogen fixation that require the transcription of
multiple sets of genes regulated in bacteria?
(A) Multiple operons are simultaneously induced.
(B) Cascades of sigma factors synthesized in a temporal order, allow the turning on of successive sets of genes.
(C) The end product of one operon is used as an inducer of the next operon in sequence.
(D) There are single operons consisting of many genes for each of these processes.

27. As a general principle of gene regulation through operons, regulatory genes encode
(A) trans-acting proteins that interact with cis-acting DNA elements.
(B) cis-acting proteins that interact with cis-acting DNA elements.
(C) cis-acting proteins that interact with trans-acting DNA elements.
(D) trans-acting proteins that interact with trans-acting DNA elements.

28. In the regulation of the trp operon, tryptophan acts as a(n)__________.
(A) repressor (B) attenuator (C) activator (D) corepressor

29. The transition from transcriptional initiation to elongation involves
(A) binding of sigma factor. (B) release of sigma factor.
(C) release of RNA polymerase from DNA. (D) binding of RNA polymerase to DNA.

30. A tRNA that recognizes a nonsense codon and inserts an amino acid where protein synthesis should have stopped is called a(n)______________.
(A) nonsense tRNA (B) suppressor tRNA (C) revertant tRNA (D) excision tRNA

31. In the modification of eukaryotic mRNA, a "cap" consisting of a/an _________and a tail consisting of_________are usually added to the transcript.
(A) acetyl group, multiple cytosines (B) multiple guanines, methyl group
(C) multiple thymines, acetyl group (D) methyl group, multiple adenines

32. RNA molecules that can act as enzymes and catalyze specific biochemical reactions are known as_________.
(A) donors (B) splice acceptors (C) ribozymes (D) tRNAs

33. The retroviruses, including HIV, are unique because they do reverse __
(A) replication. (B) transcription. (C) splicing. (D) translation.

34. There are _________usually found in the genetic code.
(A) 3 start codons and 1 stop codon
(B) 2 start codons and 2 stop codons
(C) 1 start codon and 3 stop codons
(D) 0 start codons and 4 stop codons

35. The appearance of a novel phenotype resulting from the substitution of a single base pair might be due to
(A) change in the amino acid sequence only.
(B) change in the amount of protein expressed.
(C) alteration in a gene that codes for a nontranslated RNA.
(D) All of the choices are possible consequences of a single base pair substitution.

36. The ribosome has three distinct sites E, P and A. During elongation of a protein, in which site is the growing peptide chain found?
(A) E site
(B) P site
(C) A site
(D) Any site, it makes not difference.

37. When bacteria are grown in the presence of lactose, (A)CAMP-CRF protein binds upstream of the promoter and increases transcription through recruitment of RNA polymerase. (B)CAMP-CRF protein is bound to lactose and is active and activates transcription through physical interference with the repressor. (C)the lac repressor is bound to allolactose, is now inactive and unable to bind the operon; thereby allowing RNA polymerase access to initiate transcription. (D) the lac repressor is bound to allolactose, is now inactive and unable to bind the operon; thereby allowing CAP protein access to the promoter and increasing the rate of transcription.

38. In the lac operon, which region of the operon does the repressor bind?
(A) Promoter
(B) Operator
(C) CAMP-CRF binding site
(D) +1 start of transcription

39. TFIID is one of the basal transcription factors to bind the promoter during the assembly of the pre-initiation complex, which of
the following statements about TFIID is FALSE?
(A)TFIID distorts the DNA duplex when it binds.
(B)TFIID binds the TATA box in promoters.
(C)TFIID binds the DNA only after basal transcription factors have bond the promoter region.
(D)TFIID binds Inr and DPE elements in promoters.

40. A characteristic of RNA polymerase in humans that is different from bacterial RNA polymerase is
(A) that in humans, there are three distinct nuclear RNA polymerases and only one in bacteria.
(B) that in bacterial RNA polymerase is directly recruited to the promoter but in human RNA polymerase is recruited to a
pre-initiation complex.
(C) that in human RNA polymerase many additional transcription factors must bind the promoter first before RNA polymerase is
recruited; whereas in bacteria only the sigma factor is required.
(D) All the above are characteristics of RNA polymerase that differ between human and bacteria.

II. Essay questions (20%): Please answer the following question as sufficient as you can.

1. Please define chromosome, plasmid, BAC vector, and YAC vector. (5%)

2. Please describe the mechanism by which a retroviral genome becomes double strand DNA. (5%)

3. Eukaryotes have three RNA polymerases. What are they and what does each do? (3 %)

4. Why is the lactose operon not induced in the presence of both lactose and glucose? (2%)

5. What is CPSF? & its unctions? (5%)