Biology units & topics
Tap a unit to see its topics. Every topic has free notes, a diagram, quizzes and flashcards.
GCSE Biology revision covers everything from the microscopic world of cells to whole ecosystems. Whether you're studying AQA, Edexcel, or OCR, you'll need to master topics like cell biology, organisation, infection and response, bioenergetics, homeostasis, inheritance, variation, ecology, and key practical skills.
The GCSE Biology exam is split across two papers. Paper 1 typically covers cell biology, organisation, infection, and bioenergetics. Paper 2 covers homeostasis, inheritance, variation, evolution, and ecology. Both papers include a mix of multiple-choice, short-answer, and extended-response questions worth 6 marks or more.
Tap a unit to see its topics. Every topic has free notes, a diagram, quizzes and flashcards.
A simple, proven loop that works for every topic on this page — and beats re-reading your notes every time.
GCSE Biology is visual. Practise drawing and labelling cells, the heart, the nervous system pathway, and DNA replication from memory. If you can draw it and label it without looking, you understand it. Examiners frequently ask for labelled diagrams worth 3-4 marks.
Break every biological process into numbered steps. For example, 'describe how a reflex arc works' should be: 1) stimulus detected by receptor, 2) electrical impulse along sensory neurone, 3) relay neurone in spinal cord, 4) motor neurone, 5) effector responds. This step-by-step approach is exactly what mark schemes reward.
GCSE Biology topics overlap heavily. Photosynthesis connects to ecosystems and food chains. Enzymes connect to digestion and metabolism. The nervous system connects to homeostasis. Making these links helps you answer application questions where knowledge from multiple topics is needed.
Biology has more specialist vocabulary than any other GCSE science. Words like mitosis, osmosis, homeostasis, and phagocytosis must be spelled correctly and defined precisely. Spaced repetition flashcards are the most efficient way to lock these in long-term.
Wherever you are in your GCSEs, here's the best place to pick up Biology.
Just starting GCSE content? Begin with the first unit — it underpins almost everything else in the Biology course.
Start from the beginningWorking through the course? Follow the units in order and learn one new topic at a time, testing as you go.
Browse all unitsExams approaching? Focus on the high-frequency topics examiners ask most, and drill them with quizzes and past questions.
See top exam topicsGCSE Biology is assessed across 8 written papers.
25 topics · Biology Paper 1
23 topics · Biology Paper 1
16 topics · Biology Paper 1 (B1–B3)
11 topics · Biology Paper 1 (B1–B3)
28 topics · Biology Paper 2
24 topics · Biology Paper 2
10 topics · Biology Paper 2 (B4–B6)
15 topics · Biology Paper 2 (B4–B6)
PrepWise covers 53 GCSE Biology topics across AQA, Edexcel and OCR. Each topic includes revision notes, exam-style questions, and flashcards.
Yes. All 53 topics, 1,095+ exam-style questions, and 854 flashcards are free during alpha. No card required, no trial period.
PrepWise covers AQA, Edexcel and OCR for GCSE Biology. You can select your board during setup and the content, questions, and daily plan adapt to your specification.
The highest-frequency GCSE Biology topics are cell structure, cell transport (osmosis and diffusion), the nervous system, homeostasis (blood glucose and thermoregulation), inheritance (Punnett squares), and ecosystems. These appear in almost every past paper sitting across AQA, Edexcel and OCR.
For students and parents — from Year 10 through to exam day
GCSE Biology revision covers everything from the microscopic world of cells to whole ecosystems. Whether you're studying AQA, Edexcel, or OCR, you'll need to master topics like cell biology, organisation, infection and response, bioenergetics, homeostasis, inheritance, variation, ecology, and key practical skills.
The GCSE Biology exam is split across two papers. Paper 1 typically covers cell biology, organisation, infection, and bioenergetics. Paper 2 covers homeostasis, inheritance, variation, evolution, and ecology. Both papers include a mix of multiple-choice, short-answer, and extended-response questions worth 6 marks or more.
Effective GCSE Biology revision means understanding processes — not just memorising facts. Examiners reward students who can explain why osmosis happens, not just define it. Around 15% of marks come from maths skills (calculating magnification, interpreting graphs, analysing data), so practising these is essential for a strong grade.
All three main exam boards cover similar GCSE Biology content, but the structure and emphasis differ. Knowing your board helps you target your GCSE Biology revision more effectively.
The most popular board for GCSE Biology. Two papers, each 1 hour 45 minutes, 100 marks. Strong emphasis on required practicals — there are 10 that can be examined directly. AQA tends to ask more application questions where you apply knowledge to unfamiliar contexts.
Two papers, each 1 hour 45 minutes, 100 marks. Edexcel includes more mathematical content than AQA — expect graph interpretation and calculations in almost every section. Their 6-mark questions often require you to plan or evaluate an experiment.
Two papers, each 1 hour 45 minutes, 90 marks. OCR organises content into slightly different topic groups and includes PAG (Practical Activity Group) questions. They test practical skills through exam questions rather than separate practical assessments.
A complete gcse biology revision plan from Year 10 through to the final exam — with advice for students and tips for parents at every stage.
Start your GCSE Biology revision early by keeping up with classwork. After each topic, spend 20 minutes reviewing your notes and answering 5 flashcard questions. Focus on understanding core concepts like cell structure, enzymes, and the digestive system. Don't worry about past papers yet — build your foundation first. Parents: check your child knows which exam board their school uses (AQA, Edexcel, or OCR) and has access to the correct specification.
By now you've covered most of the GCSE Biology specification. Start connecting topics together — for example, how enzymes link to digestion, which links to food tests. Begin doing past paper questions by topic (not full papers yet). Focus on Paper 2 topics as they're taught, but keep reviewing Paper 1 material weekly. Create revision cards for key definitions, processes, and required practical methods.
This is when serious GCSE Biology revision should begin. Work through every topic systematically and rate your confidence. Spend extra time on weak areas — if you can't explain a process to someone else, you don't understand it well enough. Start practising 6-mark extended-response questions, as these are where many students lose marks. Learn the command words: 'describe' means say what happens, 'explain' means say why it happens.
Your mock exams are the most valuable GCSE Biology revision tool you'll get. Do them under timed conditions and then go through every mark you dropped. The questions you got wrong in mocks are exactly what to focus on for the next three months. Parents: don't panic about mock results — they're a diagnostic tool, not a prediction. Ask your child which topics they found hardest, not what grade they got.
Now shift your GCSE Biology revision to exam technique. Do full past papers under timed conditions every week. Focus on the 15% of marks that come from maths: practise magnification calculations, percentage change, mean and standard deviation. Review all 10 required practicals (AQA) — know the method, variables, and how to evaluate results. Use spaced repetition for definitions and key terms you keep forgetting.
In the final weeks of GCSE Biology revision, focus on active recall — not re-reading notes. Test yourself daily with flashcards and past paper questions. Prioritise topics with the highest exam frequency (cell transport, homeostasis, inheritance) but don't neglect ecology and evolution, which students often revise last and score worst on. The night before: read through your key equations and required practical summaries, then get a proper night's sleep.
GCSE Biology is visual. Practise drawing and labelling cells, the heart, the nervous system pathway, and DNA replication from memory. If you can draw it and label it without looking, you understand it. Examiners frequently ask for labelled diagrams worth 3-4 marks.
Break every biological process into numbered steps. For example, 'describe how a reflex arc works' should be: 1) stimulus detected by receptor, 2) electrical impulse along sensory neurone, 3) relay neurone in spinal cord, 4) motor neurone, 5) effector responds. This step-by-step approach is exactly what mark schemes reward.
GCSE Biology topics overlap heavily. Photosynthesis connects to ecosystems and food chains. Enzymes connect to digestion and metabolism. The nervous system connects to homeostasis. Making these links helps you answer application questions where knowledge from multiple topics is needed.
Biology has more specialist vocabulary than any other GCSE science. Words like mitosis, osmosis, homeostasis, and phagocytosis must be spelled correctly and defined precisely. Spaced repetition flashcards are the most efficient way to lock these in long-term.
These come straight from examiner reports — the mistakes that cost students marks every year.
Confusing diffusion, osmosis, and active transport — learn the specific definitions and when each occurs.
Writing 'it needs energy' without specifying whether a process is active or passive transport.
Forgetting to include units in calculations — magnification has no units, but concentration is in mol/dm³.
In 6-mark questions, listing facts instead of building a logical explanation with connectives like 'this means that' and 'as a result'.
Mixing up mitosis (growth, 2 identical cells) and meiosis (gametes, 4 different cells).
As parents of GCSE students ourselves, we know how hard it is to support revision without being overbearing. Here's what actually helps with gcse biology revision at home.
Ask your child to teach you a topic — if they can explain osmosis or the immune response clearly to a non-scientist, they understand it. This is more useful than asking 'have you revised?'
Help them create a revision timetable that covers all Biology topics, not just the ones they enjoy. Students naturally avoid their weak areas, which is exactly where the marks are.
GCSE Biology requires regular, short revision sessions rather than last-minute cramming. 25-minute focused sessions with breaks are more effective than 3-hour marathons.
If your child's school uses AQA, the 10 required practicals are examined directly. Make sure they know the method, variables, and evaluation for each one — this is worth around 15% of the total marks.
53 topics, all aligned to your exam board — learn, quiz and test your way through them.
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