Exam technique
AQA GCSE Biology command words: the words that quietly decide your marks
You can know the Biology and still lose marks if you answer the wrong question. Command words tell you what the examiner wants you to do. "Describe" and "explain" are not the same job, and AQA marks them differently.
Quick takeaways
- Describe = say what happens or what the pattern is. Explain = give the reasons why.
- Compare means write about both things being compared — similarities, differences, or both. Evaluate means argue both sides and reach a conclusion.
- Suggest means apply what you know to an unfamiliar situation — you are not expected to have learnt it.
- Match the length and type of answer to the command word and the marks available.
Why command words matter more than they look
Every AQA question opens with a command word, and it is doing a job. It tells you the type of answer that earns marks. Students who lose marks often know the content perfectly well; they just answered a "describe" question with reasons, or an "explain" question with a list of observations and no biology behind them.
A quick rule of thumb: read the command word, then check the marks. One mark usually wants one clear point. A six-mark "explain" wants linked reasoning, not six facts in a row.
AQA evidence
AQA Paper 1 reports specifically warn that students often describe when asked to explain, explain when asked to describe, and fail to make proper comparisons. Command words are not decoration; they decide the shape of the answer.
Describe vs explain: the one that costs the most marks
This pair causes more lost marks than any other. Describe asks what is happening, including any pattern or trend in data. Explain asks why it is happening — the reason or mechanism behind it.
- Describe the graph: "The rate increases until 40 degrees, then falls sharply." State the pattern and quote numbers with units.
- Explain the graph: "The rate increases because more enzyme-substrate collisions occur, then falls because the enzyme denatures and the active site changes shape." Now there is a reason.
- If your sentence does not contain a "because", "so", or "due to", it is probably a describe, not an explain.
The short-answer words: name, state, give, identify
These ask for a brief, factual answer with no explanation. A word or a short phrase is enough. Writing a paragraph wastes time you will want later and does not earn extra marks.
Don’t over-answer
If a one-mark question says "Name the gas produced", write the gas. You do not need to explain the entire reaction. Save the detail for the questions that reward it.
Compare, evaluate, and justify: more than one side
These words trip students up because a one-sided answer cannot score full marks. Each one expects you to weigh things up.
- Compare: give similarities and/or differences, and mention both things in the same sentence. "Mitosis produces two cells, whereas meiosis produces four" is a comparison. "Mitosis produces two cells" on its own is not.
- Evaluate: give points for and against, then reach a conclusion or judgement based on the evidence. A bare list with no conclusion usually drops the final marks.
- Justify: support a choice or statement with reasons or evidence. You are arguing a case, not just stating it.
Suggest: the word students panic about for no reason
Suggest means apply your knowledge to an unfamiliar context. AQA does not expect you to have learnt the exact answer. They want a sensible, biologically reasonable response based on what you do know. A "suggest" question is permission to think, not a sign you missed a lesson.
How to handle it
Find the biology you do recognise inside the unfamiliar situation, then apply it. If a question describes an organism you have never met, the principles of adaptation, enzymes, or exchange surfaces still apply.
The maths words: calculate, determine, estimate
These signal a numerical answer. Calculate means use the numbers in the question to work out a value, and you should show your working so method marks are available even if the final figure slips. Determine means use the data or information given to reach an answer. Estimate means an approximate value is acceptable, often from a graph or rounded figures.
- Always show working — examiners credit the method, not just the final number.
- Include units in the final answer unless the question already gives them.
- Check whether the question wants a fraction, percentage, ratio, or decimal.
Find the matching notes
Want the topic broken down more simply? Use our AQA GCSE Biology revision notes to find the matching topic notes and practise the content in smaller pieces.