AQA A-Level Biology Paper 2, June 2025
Every question from AQA A-Level Biology Paper 2, June 2025 (7402): 10 questions, 91 marks, each with its mark scheme and topic.
- Question 1 7 marks
Explain stages of cellular respiration including glycolysis, link reaction, Krebs cycle, and the effects of an electron transfer chain inhibitor in yeast.
Biology · 3.5 Energy transfers in and between organisms (A-level only)
- Question 2 8 marks
Answer questions on homeostasis, cell dehydration due to high blood glucose, the mechanism of glucagon, negative feedback in blood pH control, and the physiological response to exercise.
Biology · 3.2 Cells · 3.6 Organisms respond to changes in their internal and external environments (A-level only)
- Question 3 6 marks
Describe how to determine dry mass using an oven and balance, calculate energy released in kJ g⁻¹ from calorimetry data, and explain how above-optimum temperatures reduce biomass using net primary production.
Biology · Practical skills · 3.5 Energy transfers in and between organisms (A-level only) · Experimental design · Data analysis
- Question 4 10 marks
Explain the effect of an inversion mutation on protein structure, evaluate clinical trial data for a haemophilia A gene therapy, and calculate the inheritance probability of an affected son.
Biology · Practical skills · 3.1 Biological molecules · 3.7 Genetics, populations, evolution and ecosystems (A-level only) · 3.8 The control of gene expression (A-level only) · Data analysis
- Question 5 7 marks
Explain phenotype, suggest reasons why observed phenotypic ratios differ from expected, and explain autosomal linkage and crossing over from cross data.
Biology · 3.7 Genetics, populations, evolution and ecosystems (A-level only)
- Question 6 10 marks
Identify structures of a motor neurone, explain how demyelination affects reflex response times, explain how atropine increases heart rate via the parasympathetic nervous system, and calculate the required dosage of atropine using lean body weight.
Biology · Practical skills · 3.6 Organisms respond to changes in their internal and external environments (A-level only) · Data analysis
- Question 7 11 marks
Evaluate an investigation on Gammarus pulex response to light intensity in a choice chamber, identify the taxis behaviour, formulate a null hypothesis, and interpret chi-squared results.
Biology · Practical skills · Required Practicals · 3.6 Organisms respond to changes in their internal and external environments (A-level only) · Experimental design · Data analysis · A-Level practicals (7–12)
- Question 8 10 marks
Calculate the age of an embryo from mutation rate data, explain why prokaryote proteomes are easier to determine than eukaryote proteomes and how this aids disease prevention, and evaluate evidence linking VNTR repeats to breast cancer risk.
Biology · Practical skills · 3.2 Cells · 3.4 Genetic information, variation and relationships between organisms · 3.8 The control of gene expression (A-level only) · Data analysis
- Question 9 7 marks
Calculate the difference between observed and expected cystic fibrosis cases in 2022, define a DNA probe, and deduce family members' genotypes from gel electrophoresis bands.
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 10 15 marks
Explain animal biodiversity, the impact of abiotic factors on recycling rates, the role of bacteria in the nitrogen cycle, the process of secondary succession, and farming practices preventing succession in tropical rainforests.
Biology · 3.4 Genetic information, variation and relationships between organisms · 3.5 Energy transfers in and between organisms (A-level only) · 3.7 Genetics, populations, evolution and ecosystems (A-level only)