AQA A-Level Biology Paper 3, June 2025
Every question from AQA A-Level Biology Paper 3, June 2025 (7402): 7 questions, 78 marks, each with its mark scheme and topic.
- Question 1 8 marks
Describe binary fission in bacteria, calculate percentage increase in bacterial population from log10 data, and explain how an ATP synthase inhibitor kills mycobacteria.
Biology · Practical skills · 3.2 Cells · 3.5 Energy transfers in and between organisms (A-level only) · Data analysis
- Question 2 9 marks
Identify nephron features, explain why proteins are not in urine, and evaluate a claim relating high-protein diet to kidney damage using rat study data.
Biology · Practical skills · 3.6 Organisms respond to changes in their internal and external environments (A-level only) · Data analysis · Uncertainty and evaluation
- Question 3 8 marks
Use the life cycle and mark-release-recapture data of the tansy beetle (Chrysolina graminis) to identify genera, justify sampling methodology, estimate population size, and suggest control variables.
Biology · Practical skills · 3.4 Genetic information, variation and relationships between organisms · 3.7 Genetics, populations, evolution and ecosystems (A-level only) · Experimental design · Data analysis
- Question 4 7 marks
Draw the structure of an amino acid, identify correct statements about protein structure, calculate antibody concentration over time, and evaluate an investigation into age-related immune responses.
Biology · Practical skills · 3.1 Biological molecules · 3.2 Cells · Data analysis · Uncertainty and evaluation
- Question 5 6 marks
Suggest why the Hardy–Weinberg equation cannot be used for CLP allele frequencies, describe the effect of DNA methylation on CDH1, and evaluate evidence for the 'two-hit' model.
Biology · Practical skills · 3.7 Genetics, populations, evolution and ecosystems (A-level only) · 3.8 The control of gene expression (A-level only) · Data analysis
- Question 6 15 marks
Evaluate a dissection drawing of the human gas exchange system, describe the mechanism of inspiration, calculate lung volume from spirometer data, and evaluate clinical trial data for lung disease treatments.
Biology · Practical skills · Required Practicals · 3.3 Organisms exchange substances with their environment · Experimental design · Data analysis · AS practicals (1–6)
- Question 7 25 marks
Write a 25-mark synoptic essay on either the importance of condensation and hydrolysis reactions in biological systems, or the importance of responses to changes in the internal and external environment of organisms.
Biology · 3.1 Biological molecules · 3.6 Organisms respond to changes in their internal and external environments (A-level only)