A region depends on a cereal crop as a major source of food. Scientists compared a population of genetically identical crop plants with a population of genetically varied crop plants.
Before a new pathogen was introduced, each population produced 6.0 tonnes of food.
| Crop plant population | Plants infected after 12 weeks (%) | Food produced after 12 weeks (tonnes) |
|---|---|---|
| Genetically identical | 90 | 1.5 |
| Genetically varied | 35 | 4.8 |
Calculate the percentage decrease in food produced by the genetically identical population after the pathogen was introduced.
Explain, using the data and ideas about genetic variation, why growing the genetically varied crop plants would reduce the threat to food security.
87 exam-style questions on AQA GCSE Biology 7.5 Food production, covering 7.5.1 Factors affecting food security, 7.5.2 Farming techniques, 7.5.3 Sustainable fisheries, and 7.5.4 Role of biotechnology. Each one has a worked solution and a mark scheme showing where the marks go.