A gene from a species of moss codes for a protein that helps plant cells remain healthy when little water is available.
Scientists carry out three attempts to transfer this gene into lettuce cells. After each attempt, 200 cells are tested for the transferred gene. In each batch, 20 plants are then grown from cells containing the transferred gene. These plants are given 20% of the usual water supply for 10 days.
| Batch | Cells containing the transferred gene, out of 200 | Plants remaining healthy, out of 20 |
|---|---|---|
| A | 42 | 5 |
| B | 136 | 18 |
| C | 174 | 4 |
Describe how scientists could use genetic engineering to produce drought-tolerant lettuce plants, including how the results support the choice of batch for further production.
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.