Cambridge International AS & A Level Biology (9700)
How a single gene builds a protein, how your immune system remembers a virus for years, how species change over millions of years — A Level Biology is the molecular story of life.
Checked against the official Cambridge syllabus for exams in 2025, 2026 and 2027 — and unchanged in substance for 2028–2030 · 18 October 2026
1.Quick facts
2.Why study Biology?
Cambridge's aims for this course, in plain words. By the end you should be able to:
- Understand biology deeply and do practical work accurately and safely.
- Use the scientific method — and know the limits of theories and models.
- Analyse data, judge its quality and draw sound conclusions.
- Communicate clearly with correct biological terms and conventions.
- Understand your responsibility to other people and to the environment.
- Enjoy biology and feel ready for a degree that uses it.
Based on the 'Aims' in the official syllabus.
3.Why these topics?
Inside the cell
Electron micrographs show organelles in detail; you study the molecules of life, how enzymes really work, how membranes control what enters a cell, how cells divide — and how DNA is copied and read to make proteins.
Moving things around
How water climbs a 100-metre tree, how the heart and blood vessels deliver oxygen, and how the lungs are built for gas exchange — the physiology medicine is built on.
Fighting disease
Cholera, malaria, tuberculosis and HIV/AIDS — how they spread and how they are controlled — then antibodies, vaccination and why antibiotic resistance matters so much.
Energy for life
Respiration and photosynthesis step by step — glycolysis, the Krebs cycle, ATP and the light-dependent reactions. This is how every cell is powered.
Control systems
How the body keeps blood glucose and water balance steady, how nerve impulses and synapses work, and how plants respond to their environment.
Genes, evolution and the future
Inheritance, natural selection and how new species arise; classification and conservation of endangered species; and genetic technology — from genetic engineering to gene therapy.
4.Topic map
AS Level
- 1Cell structure
- 2Biological molecules
- 3Enzymes
- 4Cell membranes and transport
- 5The mitotic cell cycle
- 6Nucleic acids and protein synthesis
- 7Transport in plants
- 8Transport in mammals
- 9Gas exchange
- 10Infectious diseases
- 11Immunity
AS Level students also study practical skills.
A Level (adds to all the AS topics)
- 12Energy and respiration
- 13Photosynthesis
- 14Homeostasis
- 15Control and coordination
- 16Inheritance
- 17Selection and evolution
- 18Classification, biodiversity and conservation
- 19Genetic technology
A Level students also study practical skills.
5.From O Level to A Level
Coming from O Level or IGCSE? The topics sound familiar — the detail is new.
| Idea | At O Level / IGCSE | At AS & A Level (this course) |
|---|---|---|
| Cells | Cell parts and their jobs | Ultrastructure from electron micrographs; mitosis and the cell cycle |
| Molecules | Food tests | Protein structure, DNA replication, transcription and translation |
| Enzymes | Temperature and pH effects | Inhibitors, Vmax and Km |
| Disease | Pathogens, antibiotics, vaccines | Named diseases (TB, malaria, HIV/AIDS, cholera), antibodies and immune memory |
| Energy | Word equations | Glycolysis, Krebs cycle, oxidative phosphorylation, Calvin cycle |
| Genes | Simple genetic crosses | Dihybrid crosses, chi-squared test, evolution, genetic technology |
6.Exam pattern
Three ways to take it
All papers are marked by Cambridge. Paper 3 is done in a laboratory at your exam centre — ask about it when you register.
7.Types of questions
Examples are written by our teachers in Cambridge style to show the type of question — they are not copied from past papers.
8.Command words
| Word | Cambridge meaning | What to do |
|---|---|---|
| Describe | state the points of a topic / give characteristics and main features | For data: trend, key figures, units. |
| Explain | set out purposes or reasons / make the relationships between things evident / provide why and/or how and support with relevant evidence | Give the biological mechanism. |
| Outline | set out main points | Brief, but cover each stage. |
| Compare | identify/comment on similarities and/or differences | Pair the points — 'X has…, whereas Y has…'. |
| Suggest | apply knowledge and understanding to situations where there are a range of valid responses in order to make proposals / put forward considerations | Unfamiliar organism or data — reason it through. |
| Discuss | write about issue(s) or topic(s) in depth in a structured way | Several sides, organised clearly. |
Meanings are quoted from the 'Command words' table in the official syllabus.
9.What examiners reward
Applying biology is worth as much as knowing it (40% each) — practise past-paper data questions, not just notes.
10.Grades
AS Level: a, b, c, d, e. Full A Level: A*, A, B, C, D, E. 'Ungraded' means below the lowest grade and is not shown on the certificate.
What it took in June 2026 (full A Level, all five papers)
| Grade | Marks out of 260 | Roughly |
|---|---|---|
| A* | 190–202 | about 73–78% |
| A | 165–177 | about 63–68% |
| B | 140–152 | about 54–58% |
| C | 120–131 | about 46–50% |
| D | 100–111 | about 38–43% |
| E | 80–91 | about 31–35% |
Minimum weighted marks out of 260 in June 2026; the range covers the different paper variants. For AS Level alone (out of 130) an 'a' needed about 86–92.
Medicine and dentistry usually ask for A/A* grades in Biology and Chemistry. Check each university's own requirements.
11.Practical skills
- Paper 3 includes microscopy: plan diagrams, cell drawings and measuring with an eyepiece graticule and stage micrometer.
- Practise the biochemical tests (e.g. Benedict's, biuret, iodine, emulsion) and semi-quantitative methods.
- Record raw data in tables with units; calculate means and rates correctly.
- Paper 5: identify variables, describe a clear method and risk assessment, and choose the right statistical test.
- Evaluate with specific, practical improvements — not just 'repeat it'.
12.Books & resources
Cambridge says textbooks endorsed for the syllabus from 2022 are still suitable — including for 2028–2030.
13.Common mistakes
- Vague terms: 'energy is produced' instead of 'ATP is synthesised'.
- Describing data without quoting figures and units, or explaining when asked only to describe.
- Confusing transcription with translation, or DNA replication with protein synthesis.
- Drawing shaded or sketchy diagrams in Paper 3.
- Forgetting that the chi-squared test compares observed with expected results.
Tips from our teachers.
14.Study plan
- Year 1 (AS), term 1Cell structure, biological molecules, enzymes, membranes (1–4).
- Year 1, term 2Cell cycle, nucleic acids and protein synthesis, transport in plants and mammals (5–8).
- Year 1, term 3Gas exchange, infectious diseases, immunity (9–11); AS past papers and Paper 3 practice.
- Year 2 (A2), term 1Respiration, photosynthesis, homeostasis (12–14).
- Year 2, term 2Control and coordination, inheritance, evolution, classification and conservation, genetic technology (15–19).
- Final monthsTimed Papers 4 and 5 weekly; essay-style answer practice; statistics drills.
Cambridge designs AS for about 180 and full A Level for about 360 guided learning hours. Add 4–5 hours a week of your own practice.
15.Where it can take you
A Level Biology leads into medicine and the life sciences.
Typical subject requirements — always check each university's own entry rules.
16.Biology in the real world
Diseases that shaped history
Cholera, malaria, TB and HIV/AIDS are all named in Topic 10 — you learn how each spreads and how communities control them.
Monoclonal antibodies
Lab-made antibodies are used both to diagnose diseases and to treat them — the syllabus asks you to outline how (Topic 11).
Gene therapy
Treating genetic disease by delivering working genes into cells is part of Topic 19 — real medicine being developed today.
Conserving endangered species
Topic 18 covers why species become endangered and how zoos, seed banks and protected areas help — think of Pakistan's Indus river dolphin.
17.Frequently asked questions
Do I need O Level Biology first?
Cambridge recommends having completed Biology or Co-ordinated Science at IGCSE / O Level standard first.
Is A Level Biology just memorising?
No — 40% of the marks are for applying, analysing and evaluating. Data questions and Paper 5 reward reasoning.
Should I take Chemistry too?
For medicine, dentistry and pharmacy, yes — most universities ask for both.
How do online students do Paper 3?
Paper 3 is taken in your exam centre's lab, so register with a centre that runs it and practise microscopy and tests beforehand.
Is the syllabus changing?
The 2028–2030 syllabus has no significant changes that affect teaching.
18.Study it with us
Live online classes with experienced Cambridge teachers, weekly quizzes and assignments in your portal, past-paper practice, and progress reports your parents can see.
19.Official sources
- Official syllabus 9700 for exams in 2025, 2026 and 2027 (PDF)
- Official syllabus 9700 for exams in 2028, 2029 and 2030 (PDF)
- Grade threshold table, June 2026 (PDF)
- Endorsed resources for 9700
Cambridge says its syllabuses and specimen materials are the final authority on the content and structure of its exams. Always check you are using the syllabus for the year you sit the exam.