A fungal pathogen causes a disease in a population of captive frogs.
Scientists removed three different molecules, U, V and W, from the surface of the fungus. Separate groups of frogs were injected with one of the molecules.
The mean concentration of antibodies that bind to the live fungus was measured before each injection and 10 days afterwards.
| Molecule injected | Mean antibody concentration before injection in mg/dm³ | Mean antibody concentration 10 days after injection in mg/dm³ |
|---|---|---|
| U | 0.6 | 14.8 |
| V | 0.7 | 0.9 |
| W | 0.5 | 0.4 |
Which molecule should the scientists use in a vaccine against the fungal pathogen?
Use the data to explain your answer.
The scientists then use the selected molecule in a vaccine.
Explain why a vaccinated frog is unlikely to develop the disease if the live fungus enters its body later.
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.