41) A new DNA strand elongates only in the 5' to 3' direction because A) DNA polymerase begins adding nucleotides at the 5' end of the template. B) Okazaki fragments prevent elongation in the 3' to 5' direction. C) the polarity of the DNA molecule prevents addition of nucleotides at the 3' end. D) replication must progress toward the replication fork. E) DNA polymerase can only add nucleotides to the free 3' end. ANS: E PTS: 1 TOP: Concept 16.2 42) Replicating the lagging strand of DNA-that is, adding bases in the 3' 5' direction-utilizes which of the following? 43) What kind of molecule or substance is the primer that is used to initiate the synthesis of a new DNA strand? 44) What is the function of topoisomerase?
45) What is the role of DNA ligase in the elongation of the lagging strand during DNA replication? A) synthesize RNA nucleotides to make a primer B) catalyze the lengthening of telomeres C) join Okazaki fragments together D) unwind the parental double helix E) stabilize the unwound parental DNA ANS: C PTS: 1 TOP: Concept 16.2 46) All of the following are functions of DNA polymerase in DNA replication except 47) Which of the following help to hold the DNA strands apart while they are being replicated? 48) Which of these mechanisms ensures that the DNA sequence in the genome remains accurate? 49) Individuals with the disorder xeroderma pigmentosum are hypersensitive to sunlight because their cells have an impaired ability to A) replicate DNA. B) undergo mitosis. C) exchange DNA with other cells. D) repair thymine dimers. E) recombine homologous chromosomes during meiosis. ANS: D PTS: 1 TOP: Concept 16.2 50) Which of the following is analogous to telomeres?
51) A eukaryotic cell lacking telomerase would 52) Which of the following statements about telomeres is correct?
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