A technician tests four methods for producing pepper plants by tissue culture. The nutrient medium and culture containers are sterilised in every method. Each method uses 20 explants.
| Method | Explant sterilised | Cutting blade sterilised | Number of cultures contaminated after 7 days | Number of plantlets formed after 28 days |
|---|---|---|---|---|
| A | yes | yes | 1 | 18 |
| B | no | yes | 14 | 5 |
| C | yes | no | 11 | 8 |
| D | no | no | 18 | 2 |
Using the data, explain why method A should be used to produce the pepper plants.
100 exam-style questions on Edexcel GCSE Biology 4.3 Selective breeding and genetic modification, covering 4.3.1 Selective breeding and its impact, 4.3.2 Tissue culture, 4.3.3 Genetic engineering overview, 4.3.4 Main stages of genetic engineering, 4.3.5 Advantages and disadvantages of GM organisms, 4.3.6 Agricultural solutions for a growing population, and 4.3.7 Evaluating genetic engineering and breeding. Each one has a worked solution and a mark scheme showing where the marks go.