CAIE A Level Biology 9700 · Nucleic acids and protein synthesis
In terms of hydrogen bonding, explain why the C-G base pair is stronger than the A-T base pair. Then, describe how this difference influences the process of semi-conservative replication, including the roles of DNA polymerase and DNA ligase and the formation of leading and lagging strands.
6 marks, so the mark scheme is looking for about 6 separate creditworthy points. Making the same point twice in different words earns it once.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
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