In a trial, 500 people were given insecticide-treated nets and 500 people were given untreated nets. After one year, 25 people in the treated group and 90 people in the untreated group had caught malaria. Which conclusion is supported by these results?
People who used treated nets were less likely to catch malaria
Treated nets prevent malaria in everyone who sleeps under one
Treated nets kill the malarial protist in the blood of the user
Untreated nets increase the risk of a person catching malaria
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.