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A-LevelBiologyEnzymes9700/12 · Oct/Nov 2023 · Q131 Mark

The graph shows the results of two experiments on the effect of increasing substrate concentration on the rate of an enzyme-catalysed reaction. One experiment was at a high concentration of enzyme and the second was at a low concentration of enzyme. All other variables were standardised. [Figure 13.1] What would limit the initial rate of reaction at point X?

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Aenzyme concentration
BpH
Csubstrate concentration
Dtemperature

✓ Correct answer

A: enzyme concentration

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About this question

Topic
Enzymes, A-Level Biology (syllabus 9700). Multiple choice, 1 mark.
Source
A-Level Biology, Oct/Nov 2023 Paper 1 Variant 2, question 13.

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