CAIE A Level Biology 9700 · Inheritance
Describe the differences between structural genes and regulatory genes, and between inducible and repressible enzymes, using the lac operon as an example of an inducible system. Present your answer as a table comparing inducible and repressible enzymes, and include an explanation of the roles of structural and regulatory genes in these systems.
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.
Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.
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