AQA GCSE Combined Science required practicals: All 21 explained

If you're sitting AQA Combined Science: Trilogy (spec code 8464), there are 21 required practicals you need to know. You don't carry any of them out in the exam. Instead, questions about method, variables, results and conclusions turn up across all six papers, and they can appear anywhere a related topic shows up.

AQA numbers the practicals 1 to 21 in one continuous run. Biology takes 1 to 7, Chemistry takes 8 to 13, Physics takes 14 to 21. The rest of this guide walks through all 21 in that order, flags which paper each sits under, and reconciles the ones that get dropped if you're on Trilogy rather than Triple.

If you're on a different board, we've got separate guides for OCR Gateway (spec A) and OCR Twenty First Century (spec B). For Edexcel 1SC0, use our Edexcel Combined Science core practicals guide instead. The language also shifts between boards: AQA says "required practicals", Edexcel says "core practicals", OCR says "PAGs" (Practical Activity Groups). Same idea, different names.

The table below lists every required practical in AQA's own 1 to 21 numbering. Each one belongs to a topic area, and questions about it tend to appear in the section of the paper that covers that topic. Each of the six papers is 1 hour 15 minutes long, worth 70 marks, and accounts for 16.7% of the overall grade.

A few patterns worth noticing when you look at the list. Biology practicals 1 to 5 sit on Paper 1 (Cell biology, Organisation, Infection and response, Bioenergetics), and 6 and 7 sit on Paper 2 (Homeostasis and response; Inheritance, variation and evolution; Ecology). On the Chemistry side, Paper 1 covers practicals 8 to 10 (Atomic structure, Bonding, Quantitative chemistry, Chemical changes, Energy changes), while Paper 2 covers 11 to 13 (Rates and extent, Organic, Chemical analysis, Earth atmosphere, Using resources). Physics Paper 1 covers 14 to 17 (Energy, Electricity, Particle model, Atomic structure), and Paper 2 covers 18 to 21 (Forces, Waves, Magnetism and electromagnetism).

There isn't a separate practical paper for AQA Combined Science. The practical-skills questions are woven through all six written papers instead.

Across the full qualification, 20% of the marks sit under AO3 (analyse information and ideas; evaluate; develop and improve experimental procedures). On top of that, AQA writes at least 15% of marks across the papers to specifically assess practical skills. In practice that means a handful of questions on every paper that look like method descriptions, variable identification, data analysis or evaluation of an unfamiliar experiment.

AQA keeps coming back to the same four question types for every required practical. The first is describing the method: listing the steps in order, naming the equipment and stating the quantities. Vague answers like "test it with a chemical" score zero. The second is identifying the variables, which means naming the independent variable (what you change), the dependent variable (what you measure), and at least two control variables, and saying how you'd control each one. The third is explaining the results using scientific knowledge: not just "the mass went up", but why. A potato gaining mass in a dilute sugar solution because water moved in by osmosis, from higher water potential to lower, for example. The fourth is evaluating the method: spot a weakness, suggest an improvement.

Six-mark extended-response questions sometimes focus on one required practical end to end. Those need a logical structure: method, science, link to the context of the question.

This is the one thing people trip over when they revise from a Triple-focused resource. Trilogy drops seven of the practicals that are present on the three separate GCSEs. The maths: Triple is 10 Biology + 8 Chemistry + 10 Physics = 28. Trilogy is 7 + 6 + 8 = 21. The seven that get dropped are the ones that only live in "biology only", "chemistry only" or "physics only" topics on Triple.

Reading through the method isn't enough. Required practicals test whether you can think like a scientist, not whether you can recite a recipe. A few things that actually move the needle:

Write the method out from memory for each practical, then check it against your notes. The steps you forgot are the ones that would have cost you marks. Pay attention to the small details AQA likes to ask about: incubating microbiology plates at 25 degrees Celsius rather than 37 (so dangerous pathogens don't thrive), taping agar lids rather than sealing them, inverting plates, controlling the volume of solution in osmosis experiments, blotting potato cylinders before weighing. That level of detail is where the method-description marks sit.

Practise drawing results tables with correct headings, units and number of decimal places. AQA often asks you to complete or draw a table, and the marks are there just for headings-with-units, consistent decimal places and the independent variable in the left column.

Sketch the graphs you'd expect for each practical. For osmosis, a line showing percentage change in mass against concentration that crosses zero at the isotonic point. For photosynthesis, a curve that rises and then plateaus. For force vs extension of a spring, a straight line through the origin until the limit of proportionality. Plotting accurately and labelling axes correctly is worth marks on its own.

Work through past paper questions on each practical. AQA recycles similar wording and structures year on year, and the mark schemes are a goldmine for the exact phrases they want you to use. Our GCSE mock exams guide walks through how to use mock periods to test your recall across all 21 practicals in one go.

Our AQA GCSE Combined Science courses cover every one of the 21 required practicals through short video lessons, worked examples and exam-style questions. Each practical gets its own lesson walking through the method, the variables, the results and the exam language. You can jump straight into the Combined Science Biology course, the Combined Science Chemistry course or the Combined Science Physics course and track your progress through the whole spec.

For a wider revision framework, our how to revise for GCSE Science guide covers paper structure, timing, and how to layer the required practicals into a week-by-week plan.