GENETICS AND EVOLUTION
GENETIC BASIS OF INHERITANCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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all tall
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all dwarf
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all intermediate forms
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1 tall:1 dwarf
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Detailed explanation-1: -The genotype of dwarf offspring: t/t. The genotype of tall offspring: T/t whose parental cross always produce offspring.
Detailed explanation-2: -A cross between pure breeding tall (TT) and dwarf (tt) plants produce all tall (Tt) plants in F1 progeny. These heterozygous tall plants produce 50% gametes with “T” allele and 50% with “t” allele. Random fusion of these gametes from two heterozygous tall plants gives tall and dwarf plants in 3:1 ratio.
Detailed explanation-3: -Therefore, option b) 1 : 2: 1 :: Tall homozygous : Tall heterozygous : Dwarf is the correct option.
Detailed explanation-4: -The phenotypic ratio between tall and dwarf plants in F2 generation is 3:1. Example of Mendel’s pea cross: If parent is heterozygous dominant then the genotype will be Tt and Tt. Now, if you will do a cross then the result you will get is: Parents: Tt x Tt.