Scientists analysed a gene controlling a characteristic in two parent moths and one of their offspring. The DNA analysis was repeated and gave the same results.
| Moth | Alleles detected |
|---|---|
| Parent 1 | A1 and A1 |
| Parent 2 | A1 and A2 |
| Offspring | A1 and A3 |
Explain how allele A3 could have arisen in this offspring.
Explain why meiosis and random fertilisation alone could not have produced allele A3.
96 exam-style questions on Edexcel GCSE Biology 3.4 Variation and the Human Genome Project, covering 3.4.1 Causes of variation, 3.4.2 Outcomes of the Human Genome Project, 3.4.3 Genetic variation within a population, and 3.4.4 Effects of genetic mutations on phenotype. Each one has a worked solution and a mark scheme showing where the marks go.