Question

What do you think Mendel would have got had he self-pollinated a tall F2 plant?

Answer 1

Part 1: Genotype of F2 generation
In Mendel’s experiment, when he crossed homozygous tall and dwarf parent plants, he had obtained heterozygous tall plants in the F1 generation. Selfing of the F1 produced the F2 generation as shown in the figure below: The tall phenotype can be expressed when a plant is having either homozygous dominant condition (TT) or heterozygous dominant (Tt).

Part 2:Selfing between two homozygous tall plants of F2 generation
If Mendel had self-pollinated homozygous tall plants of the F2 generation, he would have got all tall plants.

Part 3: Selfing between two heterozygous tall plants of F2 generation
If Mendel had self-pollinated heterozygous tall plants, he would have got tall as well as dwarf plants in the phenotypic ratio of 3:1 and genotypic ratio of 1:2:1.

Part 4: Selfing between heterozygous and homozygous tall plants of F2 generation
If Mendel would have self-pollinated heterozygous and homozygous tall plants he would have got all tall -heterozygous as well as homozygous plants, in the genotypic ratio of 1:1 respectively.