A scientist recorded the following results when investigating enzyme activity at different pH values: pH 3 (5 units), pH 5 (15 units), pH 7 (28 units), pH 9 (12 units), pH 11 (3 units). What can be concluded from these results?

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Question

A scientist recorded the following results when investigating enzyme activity at different pH values: pH 3 (5 units), pH 5 (15 units), pH 7 (28 units), pH 9 (12 units), pH 11 (3 units). What can be concluded from these results?

Accepted Answer

the enzyme has an optimum pH of approximately 7 — Award 1 mark for correct interpretation. The highest activity (28 units) occurs at pH 7, indicating this is the optimum pH. A is incorrect because the highest activity is at pH 7 (neutral), not in acidic conditions. C is incorrect because activity decreases after pH 7, showing pH does not always increase activity. D is incorrect because pH 7 shows the highest activity, not denaturation.

Answer

the enzyme has an optimum pH of approximately 7

Answer

increasing pH always increases enzyme activity

Answer

the enzyme is denatured at pH 7

Answer

the enzyme works best in acidic conditions

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