Gonorrhoea was once easily treated with penicillin. Many strains of the gonorrhoea bacterium are now resistant to penicillin. Which statement explains how this resistance arose?
Bacteria changed their own genes in response to the penicillin used
Random mutations produced bacteria that survived and then reproduced
Patients became immune to penicillin, so the bacteria were not killed
Penicillin became weaker each time that it was used as a treatment
176 exam-style questions on AQA GCSE Biology 3.1 Communicable diseases, covering 3.1.1 Communicable (infectious) diseases, 3.1.2 Viral diseases, 3.1.3 Bacterial diseases, 3.1.4 Fungal diseases, 3.1.5 Protist diseases, 3.1.6 Human defence systems, 3.1.7 Vaccination, 3.1.8 Antibiotics and painkillers, and 3.1.9 Discovery and development of drugs. Each one has a worked solution and a mark scheme showing where the marks go.