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A tall true breeding garden pea plant is crossed with a dwarf true breeding garden pea plant. When the $F_1$ plants were selfed, the resulting genotypes were in the ratio of
A
1 : 2 : 1; tall heterozygous : tall homozygous : dwarf
B
3 : 1; tall : dwarf
C
3 : 1; dwarf : tall
D
1 : 2 : 1; tall homozygous : tall heterozygous : dwarf
Explanation
$F_2$ genotypes TT : Tt : tt = 1 : 2 : 1.
Detailed Solution
Parents: Tall (TT) × Dwarf (tt); gametes T and t; $F_1$: Tt (heterozygous tall)
$F_1$ selfed: TT (homozygous tall) 25%, Tt (heterozygous tall) 50%, tt (homozygous dwarf) 25%
Genotypic ratio 1 : 2 : 1 (tall homozygous : tall heterozygous : dwarf); phenotypic ratio 3 : 1.
$F_1$ selfed: TT (homozygous tall) 25%, Tt (heterozygous tall) 50%, tt (homozygous dwarf) 25%
Genotypic ratio 1 : 2 : 1 (tall homozygous : tall heterozygous : dwarf); phenotypic ratio 3 : 1.