Emma and Anna are identical twins who were adopted by different families a few weeks after their birth. Although genetically identical, they grew up with different physical and psychological characteristics. For example, though both inherited a tendency to grow large, Anna was slim and athletic because of the active lifestyle practiced in her adoptive family. This variability can be explained by how
A) each zygote is unique.
B) longevity genes can make an individual less vulnerable to certain diseases.
C) for each genotype, a range of phenotypes can be expressed.
D) mutated genes can be a source of genetic variability.

Question

Quizplus · Accepted Answer

For each genotype, a range of phenotypes can be expressed. This means that even though Emma and Anna have the same genetic makeup, their different environments and experiences shaped their physical and psychological characteristics differently.

Emma and Anna Are Identical Twins Who Were Adopted by Different