Biology 9700 · AS & A Level · Replication and division of nuclei and cells

Replication and division of nuclei and cells — practice question

The table outlines the roles of four different proteins involved in DNA replication. Which option states the function of these proteins?

  • Ahelicase: adds DNA nucleotides to the 3' end of a growing polynucleotide strand; topoisomerase: prevents original strands reforming complementary base pairs; single-strand binding protein: enables tension caused by unwinding to be released; DNA polymerase: makes strands available as templates
  • Bhelicase: enables tension caused by unwinding to be released; topoisomerase: prevents original strands reforming complementary base pairs; single-strand binding protein: makes strands available as templates; DNA polymerase: adds DNA nucleotides to the 3' end of a growing polynucleotide strand
  • Chelicase: enables tension caused by unwinding to be released; topoisomerase: makes strands available as templates; single-strand binding protein: adds DNA nucleotides to the 3' end of a growing polynucleotide strand; DNA polymerase: prevents original strands reforming complementary base pairs
  • Dhelicase: makes strands available as templates; topoisomerase: enables tension caused by unwinding to be released; single-strand binding protein: prevents original strands reforming complementary base pairs; DNA polymerase: adds DNA nucleotides to the 3' end of a growing polynucleotide strand

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