0653.B5.1.02 — Describe and explain enzyme action with reference to: the active site, enzyme- substrate complex, substrate and product: past paper questions
Real questions on 0653.b5.1.02 — describe and explain enzyme action with reference to: the active site, enzyme- substrate complex, substrate and product
The newest 9 of 9 written questions. Open one to see it on the real paper.
- 0653/42 · May/June 2025 · Q1c[3]
Fig. 1.2 is a graph of the effect of pH on the activity of an enzyme found in the mouth. enzyme activity 2 3 4 5 6 7 8 9 10 11 pH Fig. 1.2 Explain why this enzyme stops working at pH 11.
See it on the paper → - 0653/61 · May/June 2025 · Q2[7]
Invertase is an enzyme. Invertase breaks down the non‑reducing sugar sucrose into reducing sugars. non‑reducing sugar sucrose invertase reducing sugars Benedict’s solution is used to test for reducing sugars. The activity of invertase can be determined by measuring the time it takes for reducing sugars to form. Plan an...
See it on the paper → - 0653/32 · October/November 2024 · Q1b(ii)[2]
Fig. 1.2 is a graph showing the effect of temperature on an enzyme. enzyme activity 0 0 10 20 30 40 50 60 70 80 temperature / °C Fig. 1.2 Describe the effect of temperature on enzyme activity shown in Fig. 1.2. Include data in your answer.
See it on the paper → - 0653/43 · October/November 2024 · Q4a(i)[3]
The rate of photosynthesis in a submerged aquatic plant is measured by counting the number of gas bubbles released by the plant in 5 minutes. Table 4.1 shows the effect of temperature on the rate of photosynthesis in an aquatic plant. number of gas bubbles released in 5 minutes 10 30 20 72 30 96 40 42 50 28 60 2 Explai...
See it on the paper → - 0653/61 · May/June 2024 · Q1aiv[2]
Explain the results for test-tube A.
See it on the paper → - 0653/43 · October/November 2023 · Q4b(i)[1]
Identify the temperature at which the enzyme is the most active. temperature = °C
See it on the paper → - 0653/32 · February/March 2023 · Q1b(i)[1]
Identify the temperature in Fig. 1.2 when both enzymes have the same percentage activity value. temperature = °C.
See it on the paper → - 0653/32 · February/March 2023 · Q1b(ii)[2]
Describe the effect of temperature on the activity of enzyme K in Fig. 1.2. Use data in your answer.
See it on the paper → - 0653/12 · October/November 2022 · Q3[1]
Which biological molecules are present in the biscuit?
See it on the paper →
What examiners said
Candidates generally stated that the enzyme denatures and that the enzyme and substrate shapes will not be complementary. Some candidates also referred to the active site of the enzyme.
— Examiner report, May/June 2025, 0653/42 Q1(c) (Cambridge)
Some candidates gave full, detailed answers but others were unsure how to approach the planning task. Best practice is to consider the bullet points carefully and use these to structure the response. The most common reason for missing credit in the planning question is that the response only addresses some, but not all, of the bullet points. For full credit it is essential that each bullet point...
— Examiner report, May/June 2025, 0653/61 Q2 (Cambridge)
The majority of candidates identified the correct temperature of 10 °C.
— Examiner report, October/November 2023, 0653/43 Q4(b)(i) (Cambridge)
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