In the F2 generation of a cross, progeny having different traits are produced in the ratio 3 : 1. State whether it is a monohybrid cross or a dihybrid cross? Give one example of such a cross.

It is a monohybrid cross. A monohybrid cross is a cross between two individuals with two different alleles on one gene. It produces a phenotypic monohybrid ratio of 3:1 in the F2 generation. Whereas a Dihybrid cross produces a phenotypic Dihybrid ratio of 9:3:3:1 in the F2 generation.

For example- When pure tall plant (TT) are crossed with pure dwarf plants (tt), the offspring of the F1 generation is all tall plants (Tt). When these Tall plants cross bred with each other, they produce ‘TT’ ‘Tt’ ‘Tt’ ‘tt’ offspring i.e. tall : short = 3:1. The phenotypic monohybrid ratio in the F2 generation is 3:1.



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