Scientists made these observations about four microorganisms.
| Microorganism | Observation |
|---|---|
| P | It reproduced in a nutrient solution. |
| Q | Healthy seedlings developed a disease after it was placed on their leaves. |
| R | It was found on the leaves of both healthy and diseased seedlings. |
| S | An insect carried it between two seedlings, but neither seedling developed a disease. |
Which microorganism is a pathogen?
Microorganism P
Microorganism Q
Microorganism R
Microorganism S
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.