CAIE A Level Biology 9700 · Inheritance
Using the lac operon in Escherichia coli and gibberellin-induced gene activation in plants as examples, explain the distinction between structural genes and regulatory genes, and describe how regulatory gene products control the rate of transcription in prokaryotes and eukaryotes.
5 marks, so the mark scheme is looking for about 5 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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