Question

For the cross of axial violet and terminal white flowers, which of the following is incorrect with regards to the F2 generation?

(a) Axial violet are nine times more abundant than white flowers

(b) Axial white flowers are as abundant as terminal violet flowers

(c) Terminal white flowers are thrice abundant than the axial white flowers

(d) Terminal violet flowers are three times more abundant than terminal white flowers

The question was asked in an international level competition.

Asked question is from Inheritance of Two Genes-1 topic in section Principles of Inheritance and Variation of Biology – Class 12

Answer 1

Correct choice is (c) Terminal white flowers are thrice abundant than the axial white flowers

The best explanation: This is a dihybrid cross. The genetics is Mendelian since the traits are present on different chromosomes and do not exhibit linkage. Thus, the expected phenotypic ratio is 9 axial violet: 3 axial white: 3 terminal violet: 1 terminal white. Hence axial violet flowers are nine times more abundant than white flowers; axial white flowers are as abundant as terminal violet flowers; terminal white flowers are 1/3rd as abundant as axial white flowers and terminal violet flowers are thrice abundant than terminal white flowers.