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A-LevelBiologyEnzymesMay/June 2019Paper 1 Q101 Mark

A fixed volume of the enzyme catalase was added to a fixed volume of hydrogen peroxide solution. The diagram shows how the concentration of product changed over the course of the reaction. [Figure: Graph showing concentration of product vs time] What explains the shape of this graph?

AThe active sites become saturated.
BThe enzyme was denatured.
CThe hydrogen peroxide inhibited the reaction.
DThe substrate molecules were used up.

✓ Correct Answer

The correct answer is D. This question tests the candidate's understanding of enzymes within the Biologysyllabus. The examiner's mark scheme requires...

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Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...

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About This A-Level Biology Question

This multiple-choice question appeared in the Cambridge A-Level Biology (9700) May/June 2019 examination, Paper 1 Variant 2. It tests the topic of Enzymes and is worth 1 mark.

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