In one of his experiments with pea plants Mendel observed that when a pure tall pea plant is crossed with a pure dwarf pea plant, in the first generation, F1, only tall plants appear.
(a) What happens to the traits of the dwarf plants in this case?

(b) When the F₁ generation plants were self-fertilized, he observed that in the plants of second generation, F₂, both tall plants and dwarf plants were present. Why it happened? Explain briefly.

Question

In one of his experiments with pea plants Mendel observed that when a pure tall pea plant is crossed with a pure dwarf pea plant, in the first generation, F1, only tall plants appear.
(a) What happens to the traits of the dwarf plants in this case?

(b) When the F₁ generation plants were self-fertilized, he observed that in the plants of second generation, F₂, both tall plants and dwarf plants were present. Why it happened? Explain briefly.

Philoid · Accepted Answer

(i) Parent Cross:-

The gametes of tall plant cross with gametes of dwarf plant by the process of fertilization to form zygotes which produces various progeny in the F1 generation. Since, all the plants in F1 generation have factors Tt so all of them are tall. Small t represents recessive trait of dwarfness which is not in first generation due to presence of dominant trait T of tallness. Hence the dwarf traits are completely eliminated.

(ii)

The genotype generated are TT ,Tt ,Tt ,tt ; the first three have T – tallness dominant trait hence these three are tall trees. The third one has tt genotype that is both the factors are dwarf traits hence the plant is dwarf.