How would the replication be affected if there were no DNA gyrase (also known as topoisomerase) present in the cell? a.) Replication would proceed faster than usual, creating more mistakes and an overall reduction in fidelity. b.) Torsional strain ahead of the replication fork would eventually cause replication to stop, since it would be wound so tightly that DNA helicase could no longer separate the DNA strands. d.) Replication could only occur on the leading strand. c.) The newly synthesized chromosomes would recombine at a higher rate. What is the function of DNA ligase? Ligase connects Okazaki fragments by sealing nicks in the sugar-phosphate backbone Ligase unwinds the double helix by breaking the hydrogen bonding between the two strands at the replication fork Ligase reduces the torsional strain that builds up ahead of the replication fork as a result of unwinding Ligase prevents the formation of secondary structures within single-stranded DNA
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DNA gyrase is an enzyme that helps to relieve the torsional strain that builds up ahead of the replication fork as the DNA helicase unwinds the double helix. If there were DNA gyrase present in the cell, replication would proceed more smoothly, as the torsional Show more…
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4. How would DNA replication be affected in a bacterial cell that is lacking a DNA gyrase? 5. Arrange the following components of replication in the order in which they first act in the replication process: Ligase, DNA Polymerase I, Helicase, Gyrase, Primase, Single-strand binding protein, Initiator Proteins.
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During DNA replication, helicase 'unzips' the double-stranded DNA helix bit by bit. Why is the lagging strand synthesized in discrete sections, while the leading strand is synthesized continuously? DNA polymerase needs DNA ligase to join the Okazaki fragments together. DNA polymerase can only synthesize polynucleotide chains in the 5' to 3' direction. DNA polymerase needs a 'kick-start', as it can only extend an existing strand. DNA polymerase cannot copy both strands at once.
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