In a two-factor cross using Mendelian inheritance,if both parents are heterozygous for both traits,what will be the phenotypic ratio of their offspring?
A) 3:1
B) 1:2:1
C) 1:1
D) 9:3:3:1

Question

Quizplus · Accepted Answer

In a two-factor cross with heterozygous parents, the genotypic ratio of the offspring is 9:3:3:1. However, for the phenotypic ratio, we have to consider the expression of the traits. If the traits are dominant-recessive, then the phenotypic ratio will be 3:1. If both traits are codominant or incompletely dominant, then the phenotypic ratio will be 1:2:1. If the traits are both dominant, then the phenotypic ratio will be 9:3:3:1. Therefore, the best choice with the given information is D, which assumes that both traits are dominant and the phenotypic ratio is 9:3:3:1.

In a Two-Factor Cross Using Mendelian Inheritance,if Both Parents Are