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VCE Biology command words — worked examples of dropped marks
VCE Biology command words decide your marks. Worked describe/explain/compare/evaluate examples showing exactly what an answer missed — and how to fix it.
In VCE Biology, the content is rarely the problem — the command word is. Every short-answer question uses a verb that tells you what kind of answer earns the marks, and answering a different verb, however knowledgeably, scores little. This article works through real-style examples of marks dropped on command words; for a quick side-by-side of what each word demands, see the Biology command words reference tool.
Describe vs explain: the most expensive mix-up
'Describe' asks what happens; 'explain' asks why or how it happens. The classic lost mark is answering 'describe' on an 'explain' question.
Question (2 marks): Explain how a competitive inhibitor decreases the rate of an enzyme-catalysed reaction.
A student writes: 'It binds to the active site of the enzyme so the substrate can't get in.'
Marking (illustrative, not an official VCAA scheme): identifying that the inhibitor binds the active site earns the first mark. The second is lost — the answer stops at what happens and never explains the effect on rate. The complete chain is: the inhibitor binds the active site, so fewer enzyme–substrate complexes form, so the reaction rate decreases. The final link is the mark.
Compare and evaluate: give the examiner both sides
'Compare' wants similarities AND differences, ideally in matched pairs — a list of facts about each thing separately usually under-scores. 'Evaluate' wants a judgement backed by reasoning, not just a description. On both, students lose marks by doing half the task: describing two processes without comparing them, or listing evidence without reaching a conclusion.
A reliable technique is to count the marks and make sure your answer has at least that many distinct, relevant points — and for 'compare', that those points are genuinely comparative ('whereas', 'in contrast', 'both').
Finish the causal chain
Across all command words, the most common Biology slip is stopping before the outcome. After each sentence, ask 'so what?' until you reach the effect the question is really about. If you stop early, you have stopped before the last mark — and in Biology, that last link is almost always where the mark lives.