Question

If a mother is a non tongue roller and Father is a tongue roller, whose father was a non- roller, what is the probability of having a roller daughter?

(a) 1/16

(b) 1/2

(c) 1/4

(d) 1/8

I have been asked this question in quiz.

This intriguing question comes from Numerical Problems topic in section Mendelian Genetics of Cytogenetics

Answer 1

Right option is (c) 1/4

Best explanation: In this case the father is heterozygous as Rr and mother is homozygous recessive rr. Considering the probability of a girl child being ½ we have the probability of a roller as ½. resulted is the product of these two probabilities ½ x ½ = ¼.