Two varieties of bean plant are grown with different water supplies. Other conditions are controlled.
Table: Mean plant height after six weeks
| Variety | Low water supply / cm | High water supply / cm |
|---|---|---|
| P | 12 | 20 |
| Q | 18 | 26 |
Which conclusion is supported by the table?
Both variety and water availability influence plant height.
Only inherited differences appear to influence plant height.
Neither variety nor water availability influences plant height.
Only water availability appears to influence plant height.
40 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.