Variation & Evolution
Why organisms differ, how species change over time through natural selection.
Key Concepts
Variation & Evolution is a fundamental topic in GCSE Biology. You need to understand both the theory and how to apply it to exam questions.
Make sure you know the key definitions, can explain processes step-by-step, and understand the required practical work linked to this topic.
Higher tier students should be prepared for calculation questions and extended writing where you explain and evaluate scientific ideas in detail.
Key Terms & Definitions
- Key Term 1: The fundamental concept at the heart of variation & evolution. Make sure you can define this precisely.
- Key Term 2: A related concept that often appears in exam questions alongside variation & evolution.
- Key Term 3: An important process or principle that you need to be able to explain step-by-step.
Example Exam Questions
- [2 marks] Define the key term associated with variation & evolution and give one example.
- [4 marks] Explain how variation & evolution works, using specific terminology in your answer.
- [6 marks] Evaluate the importance of variation & evolution with reference to specific examples you have studied.
Tip: For 6-mark questions, aim for 3 developed points. Each point should have a statement, evidence/example, and explanation.
Common Mistakes to Avoid
- × Confusing key terminology or using everyday language instead of scientific/technical terms.
- × Not showing your working in calculation questions — even if your answer is wrong, method marks can save you.
- × Writing generic answers that could apply to any topic. Be specific to variation & evolution.
- × Running out of time on longer questions because you spent too long on earlier ones.
Exam Tips
- • Read the question carefully — underline command words like “explain”, “evaluate” or “calculate”.
- • The number of marks tells you how much to write. 1 mark = 1 point. 6 marks = detailed response.
- • Use past papers to practise variation & evolution questions under timed conditions.
- • Check the mark scheme after — it shows exactly what examiners are looking for.