4.What is the key difference between exonucleases and endonucleases?
(A) Exonucleases remove nucleotides from the middle of a DNA strand, while
endonucleases remove nucleotides from the ends of DNA strands.
(B) Exonucleases are found in eukaryotes, while endonucleases are found in
prokaryotes.
(C) Exonucleases are used in DNA replication, while endonucleases are used in
DNA repair.
(D) Exonucleases remove nucleotides from the ends of a DNA strand, while
endonucleases remove nucleotides from within a DNA strand.

(E) Exonucleases only act on single-stranded DNA, while endonucleases only
act on double-stranded DNA.

50. I didn't know how to use that weapon until I got some________. (A)job(B)duty (C) chance (D) training

1. A cell or organism that possesses two homologous copies of each of its chromosomes is described as: (A) Haploid (B) Triploid (C) Diploid (D) Aneuploid(E) Polyploid

2. What type of bond links nucleotides together to form a strand of DNA or RNA? (A) Hydrogen bond (B) Phosphodiester bond (C) Peptide bond (D) Glycosidic bond (E) Ionic bond

3. Which of the following best describes the function of histones ineukaryotes?(A) To negatively supercoil DNA.(B) To act as enzymes that cut and paste DNA.(C) To serve as a scaffold for RNA synthesis.(D) To package and organize DNA into nucleosomes.(E) To provide structural support to the cell membrane.

5.A researcher is using degenerate primers to amplify a gene from a newly discovered organism. They designed the primers based on a short peptide sequence from a protein that they think is encoded by the gene. What is the most likely reason that a pool of different primers is needed for PCR amplification in this scenario? (A) The use of degenerate primers ensures that the PCR reaction has multiple binding sites on the DNA template, thus amplifying the sequence more efficiently. (B) The use of degenerate primers ensures the amplification of multiple related. genes. (C) Many amino acids are encoded by multiple codons, so there are several. possible DNA sequences that could code for the same peptide sequence. (D) Degenerate primers help overcome the mispriming that can occur during PCR. (E) Degenerate primers increase the specificity of the PCR reaction.

6.What is the main advantage of using cDNA rather than genomic DNA whencreating an expression library for eukaryotic genes?(A) cDNA is easier to isolate and purify than genomic DNA.(B) cDNA is more stable than genomic DNA.(C) cDNA contains promoter sequences that are needed for expression.(D) cDNA lacks introns, which allows for proper expression in a bacterial host.(E) cDNA is double-stranded, while genomic DNA is single-stranded.

7. What is the function of dideoxynucleotides in Sanger sequencing?(A) To act as primers for DNA synthesis.(B) To label DNA fragments with fluorescent markers.(C) To cut the DNA at specific sequences.(D) To terminate DNA synthesis at specific bases.(E) To amplify the DNA for sequencing.

8.Which is true for eukaryotic RNA polymerase (RNAP) I, II and III? (A) RNAP I and II are found in the nucleoplasm, while RNAP III are found in the nucleolus. (B) Among three RNAPs, RNAP II is insensitive to alpha-amanitin. (C) The 28S, 18S and 5S ribosomal RNA are synthesized by RNAP I, while tRNA and other small RNA are synthesized by RNAP III. (D) Rpb5, Rpb7, Rpb9, Rpb10 and Rpb12 are common subunits for all three RNAPs. (E) RNAP IIA contributes to transcription elongation, while RNAP IIO is involved in the formation of pre-initiation complex.

9. Which is true for the following experimental techniques?(A) Yeast two-hybrid analysis is useful for assaying DNA-protein interactions invitro.(B) In chromatin immunoprecipitation (ChIP) analysis, formaldehyde iscommonly used for protein-DNA crosslinking.(C) Far-western blot analysis is a method to analyze protein-RNA interactions.(D) The G-less cassette assay is often used to detect protein-protein interactions.(E) A Southern blot is used to detect specific protein in a tissue sample.

10.Which statement is not true for TATA-binding protein (TBP) of eukaryoticRNA polymerases (RNAPs)?(A) RNAP III is positioned at promoter by a TFIIIC, which contains TВР.(B) For RNAP II, TBP is a component of the general transcription factor TFIID.(C) For RNAP I in human, the general transcription factor SL1 is composed ofTBP and three TAFS, and binds to the core promoter region.(D) TBP binds to the minor groove of DNA and bends consensus TATA DNA byapproximately 80 degree.(E) In yeast, TFIIB binds specifically to TBP via its C-terminal domain.