Scientists investigated variation in adult beetles of the same species.
All beetles within line P inherited the same alleles. All beetles within line Q inherited the same alleles, but these alleles were different from those in line P.
Newly hatched beetles from each line were divided between a standard food and a high-energy food. All other conditions were kept the same.
The table shows the mean measurements when the beetles became adults.
| Beetle line | Food | Mean body length in mm | Mean body mass in g |
|---|---|---|---|
| P | standard | 18.2 | 0.84 |
| P | high-energy | 18.8 | 1.12 |
| Q | standard | 21.4 | 0.96 |
| Q | high-energy | 22.3 | 1.34 |
Calculate the percentage increase in the mean body mass of line Q when the beetles were given high-energy food instead of standard food.
Give your answer to one decimal place.
Explain how the results show that adult body mass is affected by both inherited alleles and the environment.
A scientist concludes that adult body length is controlled only by inherited alleles.
Explain whether the results support this conclusion.
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.