Question

In a cross between tall pea plant with axial flowers and dwarf with terminal flowers, following number of pea plants were obtained in the F2 generation:
Tall with axial flowers = 315
Tall with terminal flowers = 108
Dwarf with axial flowers = 101
Dwarf with terminal flowers = 32
Which cross does it represent?

• A. Test
• B. Trihybrid
• C. Dihybrid
• D. Monohybrid

Hint:

A dihybrid cross involves the inheritance of two traits, with a typical 9:3:3:1 phenotypic ratio in the F2 generation.

Answer 1

The Correct Option is C

Step 1: Understanding Mendelian crosses.
A dihybrid cross involves two traits, such as height and flower position in pea plants. The 16:1 phenotypic ratio (315:108:101:32) corresponds to a dihybrid cross, where two traits are inherited independently.
Step 2: Analyzing the options.
(A) Test: Incorrect — A test cross is used to determine the genotype of an individual with a dominant phenotype.
(B) Trihybrid: Incorrect — A trihybrid cross involves three traits, which is not the case here.
(C) Dihybrid: Correct — A dihybrid cross is the correct representation of the given data, involving two traits (height and flower position).
(D) Monohybrid: Incorrect — A monohybrid cross involves only one trait, not two.
Step 3: Conclusion.
The correct answer is (C) Dihybrid, as the cross involves two traits.