Scientists are developing drug Q to treat a disease caused by a protist.
During preclinical testing, samples of infected tissue and healthy liver tissue were exposed to different concentrations of drug Q.
| Concentration of drug Q in µg/cm³ | Protists alive at the end of the test in % | Liver cells alive at the end of the test in % |
|---|---|---|
| 5 | 64 | 99 |
| 10 | 18 | 95 |
| 20 | 7 | 61 |
Explain why a concentration of 10 µg/cm³ is a better choice to take forward to tests on live animals than either 5 µg/cm³ or 20 µg/cm³.
In the live animals, drug Q killed fewer protists than the tissue test suggested.
Suggest one reason for this difference.
Further tests on live animals suggested that drug Q was safe and effective.
Explain how scientists should begin clinical trials and then test whether drug Q is effective in people.
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.