Describing instead of explaining — or explaining instead of describing
“There were a few cases of responses that failed to gain marks as the candidates described a trend when asked to explain one.”— 4BI1 Paper 1B, June 2023
How to fix: 'Describe' means state what you observe — quote specific data values from graphs or tables, name the trend (increases/decreases/stays the same), and say when any change occurs. 'Explain' means give the biological mechanism — use 'because' or 'which leads to' as a prompt to add causation. Check the command word before writing a single sentence; the two skills are never interchangeable and both can appear in the same question (e.g. 'describe and explain').