Question

I = Inflated, i = constricted. Given that the phenotype of F1 progeny is inflated pods and that the parents are true-breeding, which of the following is not a possible genotype of parents?

(a) Parent 1: II; Parent 2: ii

(b) Parent 1: II; Parent 2: II

(c) Parent 1: ii; Parent 2: ii

(d) Parent 1: ii; Parent 2: II

This question was addressed to me in quiz.

This intriguing question originated from Inheritance of One Gene-1 topic in portion Principles of Inheritance and Variation of Biology – Class 12

Answer 1

The correct answer is (c) Parent 1: ii; Parent 2: ii

The explanation is: Inflated is the dominant phenotype. Hence it can be expressed in two genotypes: II and Ii. The F1 progeny can have it in all the mentioned cases except when both parents are recessive ii.