A person eats food containing a small number of Salmonella bacteria.
Explain how the Salmonella bacteria cause the symptoms of vomiting and diarrhoea.
The person's symptoms did not begin until two days after the meal.
Suggest why the symptoms did not begin immediately.
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.