Scientists grow genetically identical copies of plant X and genetically identical copies of plant Y at two temperatures. X and Y have different genomes. Other conditions are controlled. The results are repeatable.
| Plant | Mean height at 15 °C / cm | Mean height at 25 °C / cm |
|---|---|---|
| X | 18 | 30 |
| Y | 24 | 26 |
For each plant, calculate the percentage increase in height relative to its height at 15 °C. How many times larger is this percentage for X than for Y, and what does the comparison suggest?
Six times larger; the effect of temperature on height depends on the genome.
Eight times larger; the effect of temperature on height is independent of the genome.
Six times larger; the effect of temperature on height is independent of the genome.
Eight times larger; the effect of temperature on height depends on the genome.
44 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.