When a tall pea plant (TT) is crossed with a dwarf plant (tt) what will be the `"F"_(2)` generation?

Explanation

1. When a pure tall plant (TT) is crossed with pure dwarf plant (tt) , all the offsoprings in F1 generation are tall.
2. Pure tall plant has both the factors of the same type TT"
3. Pure dwarf plant has both the factors of the same type 'tt'
4 The breed after cross pollination will have one of the factors from pure breed tall (TT) and one from pure breed dwarf (tt)
5. Thus all the plants will have the factor pair" Tt'
6. So all the plants are heterozygous tall, as 'T' is the dominationg factor.
7. On self pollin ation of these, the new breed can have any combination of T and t.
8. It can be TT, Tt, tT or tt. All of them are equal.
9. But any plant that has a T factor will be tall.
10. So in F2 generation 75% of plants are tal adn 25% of plants are dwarf. Thus the phenotype ratio is 3:1
11. Among 75% of tall plants only 25% plants are pure tall (TT) or homozygous tall remaining 50% plats are heterozygous tall (Tt, tT).
12. The ramianing 25% dwarf planta are pure or homozygous dwarf (tt).
13. So the genotype ratio is 1:2:1