AQA AS Level Biology Paper 1, June 2025
Every question from AQA AS Level Biology Paper 1, June 2025 (7401): 9 questions, 75 marks, each with its mark scheme and topic.
- Question 1 6 marks
Identify amino acid functional groups, bond type, dipeptide components, and calculate the number of amino acids in an antibody heavy chain using a given ratio.
Biology · 3.1 Biological molecules · 3.2 Cells
- Question 2 8 marks
Complete the diagram of an ATP molecule, describe ATP hydrolysis and the cellular use of phosphate, and describe the co-transport mechanism by which glucose is absorbed in the ileum.
Biology · 3.1 Biological molecules · 3.2 Cells · 3.3 Organisms exchange substances with their environment
- Question 3 8 marks
Describe the semi-conservative replication of DNA and explain the results of the Meselson-Stahl density gradient centrifugation experiment.
Biology · 3.1 Biological molecules
- Question 4 8 marks
Define genetic terms, transcribe and translate a given DNA sequence using a codon table, and explain the differing effects of a base deletion versus a base substitution mutation.
Biology · 3.4 Genetic information, variation and relationships between organisms
- Question 5 6 marks
State methods for comparing genetic diversity between species, describe valid leaf sampling techniques, and calculate the percentage uncertainty of a leaf length measurement.
Biology · Practical skills · 3.4 Genetic information, variation and relationships between organisms · Experimental design · Uncertainty and evaluation
- Question 6 9 marks
Analyze data on lung function in emphysema, calculate rate of exhalation, and evaluate epidemiological data linking smoking to COPD.
Biology · Practical skills · 3.3 Organisms exchange substances with their environment · Data analysis
- Question 7 9 marks
Identify the carbohydrate transported in phloem, explain features of starch as a storage molecule, and evaluate experimental data on the mass flow hypothesis.
Biology · Practical skills · 3.1 Biological molecules · 3.3 Organisms exchange substances with their environment · Data analysis
- Question 8 11 marks
Identify membrane components and investigate the effect of temperature on membrane permeability in beetroot using a dilution series and colorimeter.
Biology · Practical skills · Required Practicals · 3.1 Biological molecules · 3.2 Cells · Experimental design · Data analysis · AS practicals (1–6)
- Question 9 10 marks
Answer questions on the evolution of antibiotic resistance in Staphylococcus aureus, including naming the type of selection, explaining allele frequency increase, and calculating the rise in MRSA cases per 100,000.
Biology · Practical skills · 3.4 Genetic information, variation and relationships between organisms · 3.2 Cells · Data analysis