Describe how a mutation can lead to antibiotic resistance in bacteria, giving a specific example of a mutation that confers resistance.
Answer
A point mutation in the rpoB gene confers rifampicin resistance.
The correct answer is A point mutation in the rpoB gene confers rifampicin resistance. — Example: A point mutation in the rpoB gene changes the RNA polymerase β subunit, making rifampicin ineffective, leading to resistance.
Step-by-step solution
- Understand that a mutation changes the DNA sequence, creating a new allele.
- Recognise that the new allele can alter a target protein, potentially conferring an advantage.
- In the presence of the antibiotic, bacteria with the advantageous allele survive and replicate.
- Example: A point mutation in the rpoB gene changes the RNA polymerase β subunit, making rifampicin ineffective, leading to resistance.
Common mistake: Attributing resistance to natural selection alone
Concept tested: Mutation as raw material for evolution
Published · How this solution was prepared and checked
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