A woman carrying dizygotic twins drinks alcohol. The twins' blood alcohol levels are equal, yet one twin may be more severely affected than the other because their alleles for the enzyme that metabolizes alcohol differ. This is evidence that the _____ influence the effects of teratogens.

Question

Quizplus · Accepted Answer

The fact that one twin may be more severely affected than the other suggests that their alleles for the enzyme that metabolizes alcohol differ, meaning that their genes are the influencing factor in how they are affected by the teratogen (alcohol). Therefore, choice C - genes of each twin - is the best answer. Choices A, B, and D do not account for the differential effects seen between the twins.

A Woman Carrying Dizygotic Twins Drinks Alcohol