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Principles of Inheritance and Variation — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYPrinciples of Inheritance and Variation4 Marks
Question
Differentiate between Monohybrid & Dihybrid Cross.
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Answer

Monohybrid cross Dihybrid cross
1Monohybrid cross is a genetic cross between two homozygous individuals to obtain progenies with a single contrasting character1Dihybrid corss is a cross between two pure plants to obtain progenies with two contrasting characters.
2Phenotypic ratio is 3: 1 in the F₂ generation.2Phenotypic ratio is 9:3:3:1 in the F₂ generation.
3It produces a genotypic ratio of 1:2:1 in F₂ generation.3It produces a genotypic ratio of 1:2:2:4:2: 1:2:1 in F₂ generation.
4A single pair of gene is involved.4Two pair of gene is involved.

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