CAIE A Level Biology 9700 · Nucleic acids and protein synthesis
In the semi-conservative replication of a DNA double helix, two key enzymes are DNA polymerase and DNA ligase. Outline the distinct roles of these enzymes during replication, and explain how the directionality of DNA polymerase leads to the production of leading and lagging strands.
4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.
Outline means: Give the main points briefly. Less detail than describe, but every key step has to be there. One short line per step, in order. The marks are for coverage, not depth.
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