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CCEA A-Level Biology: specification, past papers and a free planner

CCEA GCE Biology is examined in six units — three at AS and three at A2. Every unit below has its own page with the topics, the assessment, the marks students usually drop and the question styles worth drilling. There are also year-by-year A2 past papers and AS past papers pages, a mark scheme guide, and a free topic planner. For the definitive wording, always check the specification published by CCEA at ccea.org.uk. BioCCEA is an independent study tool and is not endorsed by CCEA.

Build my free revision plan A2 past papers by year

AS units

AS 1 · Molecules and Cells

Biological molecules, enzymes, cell structure, transport across membranes, cell division, nucleic acids and the immune response.

  • Water, carbohydrates and lipids
  • Proteins and protein structure
  • Enzymes and rates of enzyme-controlled reactions
  • Cell structure and organelles (including microscopy)
  • The cell membrane and transport across membranes
  • Mitosis and meiosis
  • Nucleic acids, DNA replication and protein synthesis
  • Viruses and the immune response

Assessment: Written paper — structured questions plus an extended-response question carrying quality of written communication (QWC) credit.

Full AS 1 guide

AS 2 · Organisms and Biodiversity

Gaseous exchange, transport in plants and mammals, adaptation, biodiversity, classification, sampling and human impact.

  • Gaseous exchange in plants, mammals, fish and insects
  • Transport and transpiration in flowering plants
  • Transport in mammals: heart, vessels, blood and tissue fluid
  • Adaptations of organisms to their environment
  • Biodiversity, classification and sampling techniques
  • Human impact on biodiversity and conservation

Assessment: Written paper — structured questions plus an extended-response question with QWC credit.

Full AS 2 guide

AS 3 · Practical Skills in AS Biology

Planning, manipulating apparatus, recording, processing and evaluating experimental data at AS level.

  • Planning experiments: variables, controls and reliability
  • Manipulating apparatus and recording accurate results
  • Processing data: tables, graphs, means and percentage change
  • Interpreting and evaluating experimental evidence

Assessment: Assessment of practical skills — practical booklet work completed in class and a written practical-skills paper.

Full AS 3 guide

A2 units

A2 1 · Physiology, Co-ordination and Control, and Ecosystems

Homeostasis and the kidney, nervous transmission, muscle contraction, hormonal co-ordination, photosynthesis, respiration and ecosystems.

  • Homeostasis: the kidney, water balance and osmoregulation
  • Temperature control and negative feedback
  • The nervous system, nervous transmission and synapses
  • Muscle structure and contraction
  • Hormonal co-ordination in plants and animals
  • Photosynthesis: light-dependent and light-independent stages
  • Respiration and ATP production
  • Ecosystems, energy flow, nutrient cycles and succession

Assessment: Written paper — structured questions plus extended response with QWC credit.

Full A2 1 guide

A2 2 · Biochemistry, Genetics and Evolutionary Trends

Respiration and ATP, monohybrid and dihybrid inheritance, sex linkage, population genetics, natural selection, speciation and gene technology.

  • Respiration, ATP and the role of coenzymes
  • Monohybrid inheritance and genetic diagrams
  • Dihybrid inheritance, sex linkage and gene interactions
  • Population genetics, variation and natural selection
  • Speciation and evolutionary trends
  • Gene technology and its applications
  • Kingdoms, classification and evolutionary relationships

Assessment: Written paper — structured questions plus extended response with QWC credit.

Full A2 2 guide

A2 3 · Practical Skills in A2 Biology

Designing valid investigations, precision and error, statistical treatment of biological data and evaluating limitations.

  • Designing investigations with valid controls
  • Precision, accuracy and sources of error
  • Statistical treatment of biological data
  • Drawing conclusions and evaluating method limitations

Assessment: Assessment of practical skills — practical booklet work completed in class and a written practical-skills paper.

Full A2 3 guide

CCEA command words

Most dropped marks in CCEA Biology come from answering a different command word to the one printed on the paper.

Command wordWhat the examiner wants
State / Give / NameA short factual answer. No explanation needed — and no marks for adding one.
DescribeSay what happens, in order, without saying why. Trends in data need figures quoted.
ExplainGive the reason or mechanism. Every 'because' should be a separate marking point.
CompareMake linked statements about both things in the same sentence, not two separate lists.
SuggestApply what you know to an unfamiliar context. There is usually more than one creditworthy answer.
Discuss / EvaluateWeigh both sides and reach a judgement. These carry QWC credit, so structure matters.

Turn the spec into practice

BioCCEA generates quizzes, revision notes and examiner-style marking anchored to these exact CCEA units — pick a unit, answer 10 spec questions, or photograph a written answer and get it marked in CCEA mark-scheme language.

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