Question

When a homozygous tall plant is crossed with a homozygous dwarf plant, what will be the phenotypic ratio of tall and dwarf plants in F2 generation?

• A. 3:1
• B. 2:1
• C. 1:2:1
• D. 1:1

Answer 1

The correct option is A 3:1

$\bullet$A monohybrid cross is a cross between two individuals with the homozygous genotypes.
$\bullet$When a cross is made between homozygous tall(TT) plant and homozygous dwarf(tt) plant, we get heterozygous tall plant(Tt). This is called the F1 generation.
$\bullet$When a cross is made between both heterozygous tall plants, we get tall and dwarf plants in the phenotypic ratio of 3:1. This is called the F2 generation.
The genotypes will be as:
1 homozygous tall(TT)
2 heterozygous tall(Tt) and
1 homozygous dwarf(tt)