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Edexcel IGCSE Biology · Spec 3.34-3.37B

Mutation (Triple)

Mutations and mutagens, and how they can lead to variation and to cancer.

Biology revision video

Mutation (Triple)

Spec 3.34-3.37B

What you need to know

  • Recall what a mutation is
  • Explain how a mutation can change the phenotype
  • Know that most mutations have no effect

Active recall

Quick check

Answer each question before opening the answer.

How can a mutation change a protein?

It changes the base sequence, which may change the amino acid sequence, producing an altered or non-functional protein.

Are most mutations harmful?

No — most are neutral (no effect), some are harmful, and rarely one is beneficial.

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