How many papers are in Edexcel A-Level Biology A?

Three papers, all sat at the end of year 13, each 2 hours and 100 marks. Paper 1 covers Topics 1-6 (The Natural Environment and Species Survival). Paper 2 (Energy, Exercise and Co-ordination) covers Topics 1, 2, 3, 4, 7 and 8, so earlier content is examined again in a new context. Paper 3 (General and Practical Applications) draws on all 8 topics with synoptic questions and a pre-release article. Each paper is worth 33.33% of the qualification.

What topics does Edexcel A-Level Biology A cover?

8 topics. Paper 1: Lifestyle Health and Risk, Genes and Health, Voice of the Genome, Biodiversity and Natural Resources, On the Wild Side, and Immunity Infection and Forensics. Paper 2: Run for your Life (muscle physiology, respiration, exercise homeostasis) and Grey Matter (nervous system, brain, ethics of genome science).

How many core practicals are there?

18 core practicals across the course. They're examined through written questions on all three papers, and evidence from them feeds into the Practical Endorsement (Pass/Fail reported alongside the A-Level grade). Core practicals cover enzyme kinetics, microscopy, membrane permeability, aseptic technique, photosynthesis, respiration, muscle physiology, field sampling and more.

How does the Paper 3 pre-release article work?

Edexcel publishes a scientific article on their website 8 weeks before the Paper 3 exam. It's linked to one section of the paper, so you can prepare with your school copy before sitting the exam. You get a clean copy in the exam. It's an opportunity to research the topic in advance and think about how it links back to the specification content.

What is the Science Practical Endorsement?

A separate Pass/Fail reported alongside the A-Level grade. Your teacher assesses your competence across the 18 core practicals through the year (planning, apparatus use, safety, recording, analysis). It doesn't affect your A-Level letter grade, but universities often require a Pass for science courses.

What's the difference between Edexcel Biology A and Biology B?

Biology A (9BN0) is the Salters-Nuffield version, teaching biology through real-world contexts (cardiovascular disease, sport, forensics). Biology B (9BI0) teaches the same core science but in a more traditional topic-by-topic structure. Both are graded the same and both cover the same underlying content. Your school picks one.

Does Cognito cover Edexcel A-Level Biology A?

Cognito has past papers and mark schemes for Edexcel A-Level Biology A (9BN0). Use them for timed practice and check your answers against the official mark schemes as you go.

Edexcel A-Level Biology A (Salters-Nuffield) (9BN0) Specification

Edexcel A-Level Biology A (Salters-Nuffield) (9BN0) is a two-year linear qualification structured around real biological contexts, from lifestyle and health through to brain function. All three papers are sat at the end of year 13, worth 33.33% each, and Paper 3 features a pre-released scientific article issued 8 weeks before the exam.

Download the official spec (PDF)

specification overview

1. Lifestyle, Health and Risk
Paper 1
- Cardiovascular disease and risk factors
- Transport in the circulatory system
- Biochemistry of lipids, proteins and carbohydrates
2. Genes and Health
Paper 1
- Cell membranes and transport across them
- Protein synthesis and DNA structure
- Genetic disorders, inheritance and gene therapy (cystic fibrosis as a case study)
3. Voice of the Genome
Paper 1
- Cell structure, gametes and fertilisation
- Cell division (mitosis and meiosis)
- Stem cells and cell differentiation, gene expression
4. Biodiversity and Natural Resources
Paper 1
- Biodiversity measurement and adaptation
- Classification and evolution
- Plant cell structure, plant products and drug discovery
5. On the Wild Side
Paper 1
- Ecosystems and energy flow
- Photosynthesis and climate change
- Evolution, speciation and the impact of climate change on species
6. Immunity, Infection and Forensics
Paper 1
- Forensic biology (time and cause of death, DNA profiling)
- Pathogens and the immune response
- Evolutionary race between pathogens and hosts (antibiotic resistance)
7. Run for your Life
Paper 2
- Muscle physiology and skeletal structure
- Respiration (aerobic and anaerobic)
- Homeostasis and the physiology of exercise
- Performance-enhancing substances and ethical issues
8. Grey Matter
Paper 2
- The nervous system, vision and brain structure
- Brain imaging and neurological conditions
- Learning and the effect of drugs on synapses
- The Human Genome Project and GM organisms (ethics)

subject content

Paper	What's assessed	Length	Marks	Weight	Question types
Paper 1	The Natural Environment and Species Survival. Topics 1-6.	2h	100	33.33%	Multiple-choice, short open, open-response, calculations and extended writing
Paper 2	Energy, Exercise and Co-ordination. Topics 1, 2, 3, 4, 7 and 8.	2h	100	33.33%	Multiple-choice, short open, open-response, calculations and extended writing
Paper 3	General and Practical Applications in Biology. Draws on all topics (1-8) with synoptic questions. One section is underpinned by a pre-released scientific article issued 8 weeks before the exam.	2h	100	33.33%	Contextual questions with synoptic + practical-focused content

PaperPaper 1

What's assessedThe Natural Environment and Species Survival. Topics 1-6.

Length2h

Marks100

Weight33.33%

Question typesMultiple-choice, short open, open-response, calculations and extended writing

PaperPaper 2

What's assessedEnergy, Exercise and Co-ordination. Topics 1, 2, 3, 4, 7 and 8.

Length2h

Marks100

Weight33.33%

Question typesMultiple-choice, short open, open-response, calculations and extended writing

PaperPaper 3

What's assessedGeneral and Practical Applications in Biology. Draws on all topics (1-8) with synoptic questions. One section is underpinned by a pre-released scientific article issued 8 weeks before the exam.

Length2h

Marks100

Weight33.33%

Question typesContextual questions with synoptic + practical-focused content

All three papers are 2 hours and 100 marks. Paper 3's pre-release article is published online 8 weeks before the exam and underpins one section of the paper.

assessment structure

AO	What it means	Overall
AO1	Demonstrate knowledge and understanding of scientific ideas, processes, techniques and procedures.	31-33%
AO2	Apply knowledge and understanding of scientific ideas, processes, techniques and procedures in theoretical and practical contexts, including handling qualitative and quantitative data.	41-43%
AO3	Analyse, interpret and evaluate scientific information, ideas and evidence to make judgements, reach conclusions and refine practical design and procedures.	25-27%

AOAO1

What it meansDemonstrate knowledge and understanding of scientific ideas, processes, techniques and procedures.

Overall31-33%

AOAO2

What it meansApply knowledge and understanding of scientific ideas, processes, techniques and procedures in theoretical and practical contexts, including handling qualitative and quantitative data.

Overall41-43%

AOAO3

What it meansAnalyse, interpret and evaluate scientific information, ideas and evidence to make judgements, reach conclusions and refine practical design and procedures.

Overall25-27%

assessment objectives

Practical	What it involves
CP1 Effect of caffeine on Daphnia heart rate	Investigate the effect of caffeine on heart rate in Daphnia.
CP2 Vitamin C content of food and drink	Investigate the vitamin C content of food and drink.
CP3 Membrane permeability	Investigate membrane structure using beetroot pigment leakage.
CP4 Enzyme initial rate	Determine the initial rate of an enzyme-catalysed reaction.
CP5 Mitosis in root tips	Preparation and observation of mitosis in root tip cells.
CP6 Sclerenchyma, phloem and xylem microscopy	Identify sclerenchyma fibres, phloem sieve tubes and xylem vessels and their location within stems through a light microscope.
CP7 Plant mineral deficiencies	Investigate plant mineral deficiencies.
CP8 Tensile strength of plant fibres	Determine the tensile strength of plant fibres.
CP9 Antimicrobial properties of plants	Investigate the antimicrobial properties of plants, including aseptic techniques for the safe handling of bacteria.
CP10 Ecology of a habitat (quadrats and transects)	Carry out a study on the ecology of a habitat, such as using quadrats and transects to determine distribution and abundance of organisms, and measuring abiotic factors appropriate to the habitat.
CP11 Photosynthesis using isolated chloroplasts (Hill reaction)	Investigate photosynthesis using isolated chloroplasts (the Hill reaction).
CP12 Effect of temperature on enzyme initial rate (Q10)	Investigate the effect of temperature on the initial rate of an enzyme-catalysed reaction, to include Q10.
CP13 Effect of temperature on development of organisms	Investigate the effects of temperature on the development of organisms (such as seedling growth rate, brine shrimp hatch rates).
CP14 Gel electrophoresis of DNA	Use gel electrophoresis to separate DNA fragments of different length.
CP15 Effect of antibiotics on bacteria	Investigate the effect of different antibiotics on bacteria.
CP16 Rate of respiration	Investigate rate of respiration.
CP17 Effects of exercise on spirometer traces	Investigate the effects of exercise on tidal volume, breathing rate, respiratory minute ventilation and oxygen consumption using data from spirometer traces.
CP18 Habituation to a stimulus	Investigate habituation to a stimulus.

PracticalCP1 Effect of caffeine on Daphnia heart rate

What it involvesInvestigate the effect of caffeine on heart rate in Daphnia.

PracticalCP2 Vitamin C content of food and drink

What it involvesInvestigate the vitamin C content of food and drink.

PracticalCP3 Membrane permeability

What it involvesInvestigate membrane structure using beetroot pigment leakage.

PracticalCP4 Enzyme initial rate

What it involvesDetermine the initial rate of an enzyme-catalysed reaction.

PracticalCP5 Mitosis in root tips

What it involvesPreparation and observation of mitosis in root tip cells.

PracticalCP6 Sclerenchyma, phloem and xylem microscopy

What it involvesIdentify sclerenchyma fibres, phloem sieve tubes and xylem vessels and their location within stems through a light microscope.

PracticalCP7 Plant mineral deficiencies

What it involvesInvestigate plant mineral deficiencies.

PracticalCP8 Tensile strength of plant fibres

What it involvesDetermine the tensile strength of plant fibres.

PracticalCP9 Antimicrobial properties of plants

What it involvesInvestigate the antimicrobial properties of plants, including aseptic techniques for the safe handling of bacteria.

PracticalCP10 Ecology of a habitat (quadrats and transects)

What it involvesCarry out a study on the ecology of a habitat, such as using quadrats and transects to determine distribution and abundance of organisms, and measuring abiotic factors appropriate to the habitat.

PracticalCP11 Photosynthesis using isolated chloroplasts (Hill reaction)

What it involvesInvestigate photosynthesis using isolated chloroplasts (the Hill reaction).

PracticalCP12 Effect of temperature on enzyme initial rate (Q10)

What it involvesInvestigate the effect of temperature on the initial rate of an enzyme-catalysed reaction, to include Q10.

PracticalCP13 Effect of temperature on development of organisms

What it involvesInvestigate the effects of temperature on the development of organisms (such as seedling growth rate, brine shrimp hatch rates).

PracticalCP14 Gel electrophoresis of DNA

What it involvesUse gel electrophoresis to separate DNA fragments of different length.

PracticalCP15 Effect of antibiotics on bacteria

What it involvesInvestigate the effect of different antibiotics on bacteria.

PracticalCP16 Rate of respiration

What it involvesInvestigate rate of respiration.

PracticalCP17 Effects of exercise on spirometer traces

What it involvesInvestigate the effects of exercise on tidal volume, breathing rate, respiratory minute ventilation and oxygen consumption using data from spirometer traces.

PracticalCP18 Habituation to a stimulus

What it involvesInvestigate habituation to a stimulus.

required practicals

Prepare for Paper 3's pre-release article
Edexcel publishes the article online 8 weeks before the exam. Read it, annotate it, discuss it in class, then work back through the relevant biology. In the exam you'll get a clean copy but your memory of the analysis matters.
Master the 18 core practicals
Core practical questions appear on all three papers, plus feed into the Practical Endorsement (Pass/Fail). Learn the method, apparatus and expected results for each in class rather than cramming later.
Watch out for synoptic questions on Paper 3
Paper 3 pulls content from across all 8 topics. Practise linking ideas across topics (e.g. how membrane transport links to muscle contraction, or how DNA links to species evolution).
Build maths fluency
At least 10% of the marks across the three papers target maths at Level 2 or above. Practise statistical tests (chi-squared, standard deviation), rate calculations, biological indices and log scales.
Track your Practical Endorsement progress
Your teacher assesses your competence throughout the course. Some university science courses require a Pass, so check in periodically to make sure you're on track.
Use SNAB's contextual framing
Salters-Nuffield teaches biology through real-world contexts (cardiovascular disease, forensics, sport). When revising, tie the content back to the context, it's how the exam questions are framed.

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A-Level Biology A (Salters-Nuffield) (Edexcel)

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