Question

In some breeds of cattle, coat color is inherited through incomplete dominance. When two red-coated cattle are bred to one another, only red coated offspring result. When a red coated cow is mated to a white coated bull, roan (a lighter red/pink color) colored offspring result. What result would you expect from breeding two roan colored cattle?

• A. 50% red coated cattle, 50% white coated cattle
• B. 25% red coated cattle. 50% white coated cattle, 25% roan coated cattle
• C. 50% roan coated cattle, 50% white coated cattle
• D. 50% red coated cattle, 50% roan coated cattle
• E. 25% red coated cattle, 50% roan coated cattle, 25% white coated cattle

Answer 1

The correct option is E 25% red coated cattle, 50% roan coated cattle, 25% white coated cattle

The cross can be represented as shown in the figure.

The phenotypic ratio in F1 generation are:

Red coat : 1

Roan coat : 2

White coat : 1

percentage of cattle with red coat = 1/4 x 100 = 25%

percentage of cattle with roan coat = 2/4 x 100 = 50%

percentage of cattle with white coat = 1/4 x 100 = 25%

So, the correct answer is '25% red coated cattle, 50% roan coated cattle, 25% white coated cattle'.