What's in the AQA A-Level Biology Specification? A Complete Topic Guide

The AQA A-Level Biology specification (7402) is built around eight topic areas taught across two years, moving from biological molecules and cells in Year 12 through to genetics, ecosystems and gene expression in Year 13. The first four topics form the AS-level content and are examined on Paper 1, while topics five to eight are A-level only and appear on Paper 2 — with Paper 3 drawing on everything you've covered across both years. If you're trying to work out what you actually need to know for the exam, this guide breaks the whole specification down topic by topic.

The Eight Topic Areas Across Two Years

AQA groups the content into eight numbered topics rather than separate "modules," which is why the specification can feel like one long, continuous document rather than a set of neat units. Broadly, the topic areas are:

• Biological molecules — carbohydrates, lipids, proteins, enzymes, nucleic acids and ATP
• Cells — cell structure, microscopy, the cell cycle and division, transport across membranes, and the immune system
• Organisms exchange substances with their environment — surface area to volume ratio, gas exchange, and mass transport in animals and plants
• Genetic information, variation and relationships between organisms — DNA, gene expression basics, biodiversity and classification
• Energy transfers in and between organisms — photosynthesis, respiration and energy flow through ecosystems (A-level only)
• Organisms respond to changes in their internal and external environments — nervous and hormonal control, homeostasis (A-level only)
• Genetics, populations, evolution and ecosystems — inheritance, natural selection, population genetics and ecosystem dynamics (A-level only)
• The control of gene expression — gene regulation, mutation, cloning and genetic technologies (A-level only)

Each of these topic areas is itself split into several sub-sections with detailed content points, so the specification document from AQA runs to many pages once you get into the level of individual facts and required practicals. Because exact sub-topic wording and the numbering of individual content points can be updated between specification versions, always cross-check the fine detail against AQA's own published specification document (available at aqa.org.uk) rather than relying purely on summaries like this one — but the eight-topic structure above has been stable and is the one you'll see referenced by every exam board resource, textbook and revision guide for this course.

Running alongside the theory content is a set of required practical activities — AQA specifies a number of practicals that you must carry out during the course, covering skills like microscopy, dissection, chromatography, enzyme investigations and aseptic technique. These matter for two reasons: they build the "practical skills" that get examined directly in the written papers, and they're the basis of the separate endorsement of practical skills that sits alongside your A-level grade.

How the Specification Maps to Your Exam Papers

Understanding the assessment structure makes the specification much less abstract, because it tells you exactly which topics will show up where.

• Paper 1 covers topics 1–4 (biological molecules, cells, exchange, and genetic information). It's two hours long, worth 91 marks and 35% of the A-level, combining short and long answer questions with some extended response marks.
• Paper 2 covers topics 5–8 (energy transfers, response to the environment, genetics/evolution/ecosystems, and control of gene expression). It's also two hours and 91 marks (35%), and typically includes a comprehension-style question drawing on unfamiliar material.
• Paper 3 draws on all eight topics together. It's two hours, 78 marks and 30% of the total, and this is the paper where practical techniques, experimental data analysis and an extended essay question all come into play — so it rewards students who can connect ideas across the whole two years rather than recall isolated facts.

This structure has a practical implication for revision: you can't treat Papers 1 and 2 as fully separate silos, because Paper 3 will happily combine a Year 12 concept like enzyme kinetics with a Year 13 concept like gene expression in the same question. Building genuine cross-topic understanding, not just topic-by-topic memorisation, is what separates a grade B from a grade A once you're deep into the course.

A Practical Approach to Revising a Large Specification

Eight topics and two years of content is a lot to hold in your head at once, so the students who do well tend to revise systematically rather than just re-reading notes in whatever order feels comfortable. A few approaches that work well for a specification this size:

1. Build a topic checklist. Break each of the eight topics into its sub-sections and tick off each one as "not started," "revised," or "exam-ready." Seeing the whole specification laid out this way stops you from unconsciously avoiding the topics you find hardest — usually the ones you most need to revisit.
2. Use spaced revision, not last-minute cramming. Because Paper 3 mixes content from across both years, topics from Year 12 need to stay fresh well into Year 13. Revisiting a topic a week after first learning it, then again a month later, then again before mocks, embeds it far better than a single intensive session close to the exam.
3. Practise past paper questions by topic, then by paper. Start with topic-specific questions to check you understand the content in isolation, then move on to full past papers that mix topics the way Paper 3 will, so you get used to spotting which part of the specification a question is actually testing.
4. Keep required practicals separate from theory revision. Practical technique questions turn up in all three papers, so it's worth revising the method, apparatus and sources of error for each required practical as its own mini-topic, rather than assuming the practical lessons alone will be enough to remember it by exam season.
5. Revisit weak topics more often than strong ones. This sounds obvious, but without a clear record of where your gaps actually are, it's easy to keep revising what you already know because it feels productive.

How Applaa's AI Tutor Helps You Track What's Left to Revise

Given how many sub-topics sit inside those eight headline areas, the hardest part of revising AQA Biology often isn't understanding any single concept — it's keeping track of which parts of the specification you've actually covered properly. Applaa's free AI tutor is built with exactly this problem in mind: as you work through GCSE and A-Level Biology practice questions on the platform, it keeps a running picture of which specification areas you're solid on and which ones need more attention, so you're not guessing where to focus next.

Rather than working through a textbook cover to cover, you can ask Applaa's AI tutor to explain a specific sticking point — say, why oxidative phosphorylation produces the ATP yield it does, or how to interpret a Hardy-Weinberg population genetics question — and get a worked explanation pitched at A-level, followed by practice questions on that exact area. Because Applaa tracks your progress across topics over time, it naturally nudges you back towards the specification points you haven't revisited in a while, which fits neatly with the spaced-revision approach above.

If you're currently working through the AQA Biology specification and want a clearer picture of where your knowledge actually stands, it's worth trying Applaa's free AI-powered practice and tutoring tools — they're built specifically around UK exam board specifications like this one, and they're free to use, so there's no reason not to check which topics need another pass before your next set of mocks.