Hydrangea plants of the same genotype are planted in a large flower garden. Some of the plants produce blue flowers and others pink flowers. This can be best explained by which of the following?
A) the knowledge that multiple alleles are involved
B) the allele for blue hydrangea being completely dominant
C) the alleles being codominant
D) the fact that a mutation has occurred
E) environmental factors such as soil pH

Question

Quizplus · Accepted Answer

The color of hydrangea flowers is determined by the concentration of metal ions in the soil, particularly aluminum ions. In acidic soil, aluminum ions are more available, resulting in blue flowers. In alkaline soil, aluminum ions are less available, resulting in pink flowers. Therefore, the color difference is due to environmental factors like soil pH, and not genetics.

Hydrangea Plants of the Same Genotype Are Planted in a Large