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Biological molecules: Enzymes

From Mock A · Paper 1 (topics 1–4)
1.23 marks
Explain how a change in the primary structure of an enzyme could stop it working.
From Mock A · Paper 1 (topics 1–4)
1.33 marks
Figure 1 shows the rate of an enzyme-controlled reaction at different substrate concentrations, with and without an inhibitor. Use Figure 1 to identify the type of inhibitor and explain your answer.
051015200246810Substrate concentration / mmol dm⁻³Rate / a.u.No inhibitorInhibitor
Figure 1

Investigation: temperature and respiration in yeast

A student added yeast suspension to glucose solution in a water bath and collected the carbon dioxide produced over 5 minutes. Each temperature was repeated five times.
Temperature / °C20304050
Mean volume of CO₂ / cm³1.22.64.91.1
Standard deviation / cm³0.20.30.90.4
From Mock A · Paper 3 (all topics, practical skills and essay)
1.22 marks
Explain the increase in the volume of CO₂ produced between 20 °C and 40 °C.
From Mock A · Paper 3 (all topics, practical skills and essay)
1.32 marks
Explain the result at 50 °C.
From Mock C · Paper 1 (topics 1–4)
2.13 marks
Explain how a non-competitive inhibitor reduces the rate of an enzyme-controlled reaction.
From Mock C · Paper 1 (topics 1–4)
2.23 marks
Product formed by an enzyme (data are illustrative, written for this paper):
Time / s0102030
Product / µmol0183036
Calculate the initial rate of reaction and explain why the rate decreases over time.
From Mock C · Paper 3 (all topics, practical skills and essay)
1.12 marks
Investigation (written for this paper): the effect of hydrogen peroxide concentration on the rate of oxygen production by catalase in potato extract was measured.
H₂O₂ / mol dm⁻³0.51.01.52.02.5
O₂ collected in 60 s / cm³611151717
SD0.81.11.41.22.6
Calculate the rate of oxygen production at 1.5 mol dm⁻³ in cm³ min⁻¹ and in cm³ s⁻¹.
From Mock C · Paper 3 (all topics, practical skills and essay)
1.23 marks
Explain the results between 1.5 and 2.5 mol dm⁻³.
Score 0 / 21 · 0 of 8 marked

This paper is written by Plasmo in the style of the AQA A-Level Biology exam. It is not a past paper and is not produced or endorsed by the exam board.

Enzymes Exam Questions: AQA A-Level Biology | Plasmo