Assessment at a glance
AS & A Level Biology, Chemistry and Physics share an identical assessment structure and near-identical assessment objectives — only the content and a couple of AO1 bullet points differ.
| Paper | Format | Duration | Marks | Weighting |
|---|---|---|---|---|
| 1 | Multiple choice (40 questions) | 1h 15m | 40 | 31% / 15.5% |
| 2 | AS structured questions | 1h 15m | 60 | 46% / 23% |
| 3 | Advanced Practical Skills | 2h | 40 | 23% / 11.5% |
| 4 | A Level structured questions | 2h | 100 | — / 38.5% |
| 5 | Planning, Analysis and Evaluation | 1h 15m | 30 | — / 11.5% |
Three entry routes: AS Level only (Papers 1–3 in one series); A Level staged (Papers 1–3 in Year 1, then 4–5 in Year 2, carrying the AS mark forward); or A Level in one series (all five papers together). AS-only candidates are graded a–e; A Level candidates are graded A*–E.
Content overview
AS Level topics (1–11)
- Cell structure · Biological molecules · Enzymes · Cell membranes and transport
- The mitotic cell cycle · Nucleic acids and protein synthesis
- Transport in plants · Transport in mammals · Gas exchange
- Infectious diseases · Immunity
Additional A Level topics (12–19)
- Energy and respiration · Photosynthesis · Homeostasis · Control and coordination
- Inheritance · Selection and evolution
- Classification, biodiversity and conservation · Genetic technology
Assessment objectives
| Objective | AS | A Level |
|---|---|---|
| AO1 Knowledge and understanding | 40% | 40% |
| AO2 Handling, applying and evaluating information | 40% | 40% |
| AO3 Experimental skills and investigations | 20% | 20% |
Exam tips
- 1Papers 3 and 5 (practical skills) are worth 23% combined at AS and 34.5% combined at A Level — don’t neglect hands-on practice just because Papers 1, 2 and 4 feel more like ‘the syllabus.’
- 2AO2 (handling, applying and evaluating information) carries as much weight as AO1 (recall) — practice applying content to unfamiliar contexts, not just reciting definitions.
- 3For Paper 5 (Planning, Analysis and Evaluation), the context may sit entirely outside the taught syllabus — the skill being tested is experimental reasoning itself, not subject recall.
- 4Always quote answers to a sensible number of significant figures and include units — Cambridge examiner reports consistently flag this as an easy way marks are lost.
- 5A Level papers assume AS Level content as prior knowledge — keep AS topics warm even after you’ve moved on to A Level-only content.
- 6Use precise biological terminology (‘diffusion’ versus ‘active transport’, for example) — vague wording is penalised even when the underlying idea is correct.