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1.Transcription factors can be activated in several ways as well as inhibited under certain conditions. Which one of the following describes a common theme in the structure of DNA-binding proteins? 选项： A:The B: C:The D:molecules E:The F:phosphodiester G:The H:The

2.单选题]Transcription factors can be activated in several ways as well as inhibited under certain conditions. Which one of the following describes a common theme in the structure of DNA-binding proteins? 选项： A:The [object Object] C:The D:molecules E:The F:phosphodiester G:The H:The

3.Regarding DNA-guided RNA synthesis, which of the following statements is correct: （）选项： A:Only in the presence of DNA can RNA polymerase catalyze the formation of phosphodiester bonds; B:The RNA strand is synthesized from the 5′→3′ end; C:In most cases, there is only one strand of DNA as a template E. Synthetic RNA strands are never circular; D:During transcription, RNA polymerase requires primers.

4.Genes have a specific structure, one component of which is a promoter. Which of the following describes the role of the promoter for a gene? 选项： A、a protein that binds to a repressor, blocking RNA polymerase activity B、a segment of DNA that RNA polymerase binds to so that transcription is initiated C、a segment of DNA that codes for a regulatory protein D、a noncoding segment of DNA

5.() Many drugs used to treat cancers inhibit DNA replication, whereas some will inhibit the pathways required to synthesize proteins from certain genes. Which one of the following accurately describes a step leading from DNA replication to the synthesis of a protein? 选项： A:Translation of a gene generates a single-stranded RNA that is complementary to both strands of the DNA. RNA，DNA。 B:Transcription of a gene generates a single-stranded RNA that is complementary to one of the DNA strands. RNA DNA。 C:tRNA encodes the proteins during translation. TRNA。 D:mRNA encodes the proteins during transcription. MRNA。 E:rRNA encodes the proteins during transcription. RRNA。

6.Many drugs used to treat cancers inhibit DNA replication, whereas some will inhibit the pathways required to synthesize proteins from certain genes. Which one of the following accurately describes a step leading from DNA replication to the synthesis of a protein? 选项： A:Translation of a gene generates a single-stranded RNA that is complementary to both strands of the DNA. B:Transcription of a gene generates a single-stranded RNA that is complementary to one of the DNA strands. C:tRNA encodes the proteins during translation. D:mRNA encodes the proteins during transcription. E:rRNA encodes the proteins during transcription.

7.Certain drugs can intercalate between DNA bases and alter the backbone ofThe DNA. The backbone of a DNA strand is composed of which of thefollowing? Choose the one best answer. 选项： A:Phosphates and sugars B:Bases and phosphates C:Nucleotides and sugars D:Phosphates and nucleosides E:Sugars and bases

8.单选题】Many drugs used to treat cancers inhibit DNA replication, whereas some will inhibit the pathways required to synthesize proteins from certain genes. Which one of the following accurately describes a step leading from DNA replication to the synthesis of a protein? 选项： A:Translation of a gene generates a single-stranded RNA that is complementary to both strands of the DNA B: Transcription of a gene generates a single-stranded RNA that isComplementary to one of the DNA strands. C: tRNA encodes the proteins during translation. D:mRNA encodes the proteins during transcription. E: rRNA encodes the proteins during transcription.Complementary to one of the DNA strands.

9.【单选题】Many drugs used to treat cancers inhibit DNA replication, whereas some will inhibit the pathways required to synthesize proteins from certain genes. Which one of the following accurately describes a step leading from DNA replication to the synthesis of a protein? 选项： A:Translation of a gene generates a single-stranded RNA that is complementary to both strands of the DNA. B:Transcription of a gene generates a single-stranded RNA that isComplementary to one of the DNA strands. C:TRNA encodes the proteins during translation. D:MRNA encodes the proteins during transcription. E:RRNA encodes the proteins during transcription.

10.【单选题】Many drugs used to treat cancers inhibit DNA replication, whereas some will inhibit the pathways required to synthesize proteins from certain genes. Which one of the following accurately describes a step leading from DNA replication to the synthesis of a protein? 选项： A:Translation of a gene generates a single-stranded RNA that is complementary to both strands of the DNA. B:Transcription of a gene generates a single-stranded RNA that isComplementary to one of the DNA strands. C:tRNA encodes the proteins during translation. D:mRNA encodes the proteins during transcription. E:rRNA encodes the proteins during transcription.

11.29Certain drugs can intercalate between DNA bases and alter the backbone ofThe DNA. The backbone of a DNA strand is composed of which of thefollowing? Choose the one best answer. 选项： A:Phosphates and sugars B:Bases and phosphates C:Nucleotides and sugars D:Phosphates and nucleosides E:Sugars and bases

12.Which of the following about protein secondary structure is not correct? （）选项： A:it is local spatial structure of one certain part of peptide chain in protein B:it is the relative spatial position of skeleton atom on protein main chain C:amino acid sequence of protein D:it did not involve in the conformation of side chain of amnio acid E:it is hydrogen bond that maintain the stability of protein secondary structure

13.Because water is absent from the interior of the bilayer, atoms that are part of the polypeptide backbone are thus driven to form hydrogen bonds with one another.

14.The most common form of DNA damage caused by ultraviolet radiation is the formation of thymine dimers. Which of the following statements about this change in the molecular structure of DNA is wrong: ( )选项： A:Cause covalent linkage between thymines on opposite nucleotide chains; B:Can be seen as a frameshift mutation.; C:Does not terminate DNA replication; D:Can be repaired by related enzyme systems including ligase.

15.Many transcription factors, which act as dimers, bind to palindromic sequences in their target DNA. Which one of the following double-stranded DNA sequences shows perfect dyad symmetry (the same sequence of bases on both strands)? 选项：A、GAACTGCTAGTCGCB、GGCATCGCGATGCCC、TAATCGGAACCAATD、GCAGATTTTAGACGE、TGACCGGTGACCGG

16.Topoisomerase I need to break the phosphodiester bond in sugar-phosphate backbone of DNA to unwind double helix, which would consume ATP. 选项： A、正确 B、错误

17.The spatial conformation of a protein mainly depends on选项： A:α-helix and β-sheet; B:the sequence of amino acids in polypeptide chain; C:disulfide bonds in polypeptide chain; D:hydrophobic effects in polypeptide chain; E:hydrogen bonds in polypeptide chain

18.Many drugs used to treat cancers inhibit DNA replication, whereas some will inhibit the pathways required to synthesize proteins from certain genes. Which one of the following accurately describes a step leading from DNA replication to the synthesis of a protein? 选项： A:tRN B:encodes C:Transcription D:that E:strands. F:mRN G:encodes H:rRN

19.The characteristics of the leader peptide do not include ( )选项： A:Rich in negatively charged acidic amino acids; B:Low content of hydroxy amino acid; C:Rich in positively charged basic amino acids, and distributed between uncharged amino acids; D:Ability to form amphiphilic (both hydrophilic and hydrophobic) alpha helix structure.

20.Which of the following statements are correct regarding G Proteins 选项： A:A GTP-binding protein (G protein) is located on the cytoplasmic face of the plasma membrane.; B:Gs proteins can activate their downstream effectors when bound by GTP and also have the ability to hydrolyze GTP.; C:The activated G protein can change the activity of an enzyme.; D:All of the above are correct (A, B and C); E:The activated G protein cannot change the activity of an ion channel

21.Water molecules readily form hydrogen bonds with other polar molecules, and when they encounter nonpolar molecules they must form hydrogen-bonding networks with neighboring water molecules. Which of the following molecules will cause a “cage” of water to form 选项： A、2-methylpropane B、acetone C、methanol D、urea