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Chapter 9. Genetic Toxicology
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a. maintain normal cellular growth and development.
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b. exert their action in a genetically recessive fashion.
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c. are often formed via translocation to a location with a more active promoter.
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d. can be mutated to form proto-oncogenes.
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e. include growth factors and GTPases, but not transcription factors.
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Which of the following is NOT one of the more common sources of DNA damage?
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c. electrophilic chemicals.
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Which of the following pairs of DNA repair mechanisms is most likely to introduce mutations into the genetic composition of an organism?
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a. nonhomologous end-joining (NHEJ) and base excision repair.
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b. nonhomologous end-joining and homologous recombination.
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c. homologous recombination and nucleotide excision repair.
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d. nucleotide excision repair and base excision repair.
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e. homologous recombination and mismatch repair.
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Which of the following DNA mutations would NOT be considered a frameshift mutation?
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a. insertion of 5 nucleotides.
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b. insertion of 7 nucleotides.
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c. deletion of 18 nucleotides.
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d. deletion of 13 nucleotides.
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e. deletion of 1 nucleotide.
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Which of the following base-pair mutations is properly characterized as a transversion mutation?
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All of the following statements regarding nondisjunction during meiosis are true EXCEPT:
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a. Nondisjunction events can happen during meiosis I or meiosis II.
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b. All gametes from nondisjunction events have an abnormal chromosome number.
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c. Trisomy 21 (Down syndrome) is a common example of nondisjunction.
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d. In a nondisjunction event in meiosis I, homologous chromosomes fail to separate.
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e. The incorrect formation of spindle fibers is a common cause of ...