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Clostridium difficile is a bacterial species that causes disease in humans - AQA - A-Level Biology - Question 2 - 2022 - Paper 1
Question 2
Clostridium difficile is a bacterial species that causes disease in humans. Antibiotic-resistant strains of C. difficile have become a common cause of infection acq... show full transcript
Worked Solution & Example Answer:Clostridium difficile is a bacterial species that causes disease in humans - AQA - A-Level Biology - Question 2 - 2022 - Paper 1
Step 1
1. Explain how antibiotics create selection pressure
Answer
Some bacteria possess alleles that confer resistance to antibiotics. When antibiotics are used, they create selection pressure on the bacterial population, leading to non-resistant bacteria being killed off while resistant strains survive.
Step 2
2. Discuss survival and reproduction of resistant bacteria
Answer
The surviving resistant bacteria then have the opportunity to reproduce and proliferate in the absence of competition from non-resistant strains. This process increases the frequency of antibiotic-resistant bacteria in the population.
Step 3
3. Role of hospitals and weakened immune systems
Answer
Hospitals often house patients with weakened immune systems, making them more susceptible to infections. The high frequency of antibiotic-resistant strains in hospitals contributes to the spread of these infections among vulnerable patients.