CAIE A Level Biology 9700 · Enzymes
The enzyme urease catalyzes the hydrolysis of urea to ammonia and carbon dioxide. The activation energy for this reaction is lower in the presence of urease than without the enzyme.
Describe how an enzyme such as urease lowers the activation energy of a reaction. In your answer, include reference to the active site, the formation of an enzyme-substrate complex, and the lock-and-key or induced-fit hypothesis.
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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