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Edexcel IGCSE Biology · Spec 3.22, 3.33

Variation

Genetic and environmental variation, and the difference between continuous and discontinuous variation.

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Variation

Spec 3.22, 3.33

What you need to know

  • Explain what variation is
  • Describe genetic and environmental causes of variation
  • Know that most variation is caused by both together

Active recall

Quick check

Answer each question before opening the answer.

Give the difference between genetic and environmental variation, with an example.

Genetic variation is inherited (e.g. blood group); environmental variation is caused by surroundings (e.g. a scar or spoken language).

What is the difference between continuous and discontinuous variation?

Continuous varies over a range (e.g. height); discontinuous falls into distinct categories (e.g. blood group).

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