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Edexcel IGCSE Biology · Spec 3.39

Antibiotic Resistance

How antibiotic resistance develops in bacteria through natural selection, and how to reduce it.

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Antibiotic Resistance

Spec 3.39

What you need to know

  • Explain how antibiotic resistance develops
  • Link it to natural selection
  • Describe how to slow it down

Active recall

Quick check

Answer each question before opening the answer.

How do bacteria become resistant to an antibiotic?

A random mutation makes some bacteria resistant; the antibiotic kills the non-resistant ones, so the resistant survive and reproduce (natural selection).

How can we slow the spread of antibiotic resistance?

Only use antibiotics when necessary and always finish the full course.

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