Several workers arrived on an island. Blood tests showed that the workers had malaria. The island already had mosquitoes but had recorded no malaria cases for many years. Six weeks later, some residents who had not travelled developed malaria. What is the best explanation for this?
The workers released malaria protists in droplets that the residents breathed in
The residents caught malaria by direct contact with the infected workers
The mosquitoes picked up protists from infected workers and carried them to residents
The mosquitoes damaged red blood cells when biting, which created malaria protists
252 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.