Four adult volunteers each changed to a higher-energy diet for 12 weeks. They did not change their usual amount of exercise.
The table shows their body mass before and after the 12 weeks.
| Volunteer | Body mass before (kg) | Body mass after 12 weeks (kg) |
|---|---|---|
| A | 62.4 | 63.8 |
| B | 71.0 | 72.6 |
| C | 58.7 | 59.9 |
| D | 84.2 | 85.5 |
Explain how the results support the conclusion that an environmental condition can affect phenotype.
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.