CAIE A Level Biology 9700 · Enzymes
An enzyme-catalysed reaction is studied at various substrate concentrations and the initial rate of product formation is measured. Describe the relationship between substrate concentration and initial rate. In your answer, explain the meanings of Vmax and Km, and describe how a reversible competitive inhibitor would affect the values of Vmax and the apparent Km.
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.
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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