. Explain the Law of Dominance using a monohybrid cross.

Explanation

Mendel selected two plants. One with tall and the other with dwarf to get the `F_(j)` generation.
To his surprise, he got all tall plants in the F, generation.
Parents : Tall plant x
Dwarf plant `F_(j)` : rarr All tall plants
Thus the tall character appeared in the `F_(1)` generation but dwarf character did not appear. He self crossed the `F_(1)` plants and raised the `F_(2)` generation. Surprisingly he got both tall and dwarf plants in the ratio of 3:1 respectively. This ratio is called Phenotypic ratio. He repeated the experiment by taking other contrasting characters and got the same results.
`F_(j)`—> Tall plant x `F_(j)` Tall plant
`F_(2)`-t> Tall plants : Dwarf plants
3:1
Based on these results, he concluded that the tall character is dominant and the dwarf character is recessive. Then he used appropriate symbols to designate the dominant and recessive factors. He used capital letters for dominant factors and small letters of the same type to denote the recessive alleles. The monohybrid cross can be represented as below.