Scientists are testing two procedures for transferring a gene into frog embryos. The gene codes for a protein that gives frogs a wanted characteristic.
| Procedure | Stage when the gene is transferred into one cell | Embryos that develop into adults (%) | Sampled cells in each adult containing the transferred gene (%) |
|---|---|---|---|
| A | 1-cell embryo | 68 | 94 |
| B | 32-cell embryo | 91 | 6 |
Evaluate which procedure should be used to produce adult frogs with the wanted characteristic throughout the body.
80 exam-style questions on AQA GCSE Biology 6.2 Variation and evolution, covering 6.2.1 Variation, 6.2.2 Evolution, 6.2.3 Selective breeding, 6.2.4 Genetic engineering, and 6.2.5 Cloning. Each one has a worked solution and a mark scheme showing where the marks go.