Question

In a monohybrid cross between tall pea plants (TT) and short pea plants (tt), a scientist obtained only tall pea plants (Tt) in the F₁ generation. However, on selfing the F₁ generation pea plants, he obtained both tall and short plants in F₂ generation. On the basis of above observations with other angiosperms also, can the scientist arrive at a law? If yes, explain the law. If not, give justification for your answer.

Answer 1

Based on the given experiment, two laws were formulated by Mendel. They are as follows:-

Law of Dominance

• According to this law, characters are controlled by discrete units called factors that occur in pairs, with one member of the pair dominating over the other in a dissimilar pair.
• This law explains the expression of only one of the parental characters in F₁ generation and expression of both in F₂ generation.

Law of Segregation

• This law states that the two alleles of a pair segregate or separate during gamete formation in such a way that a gamete receives only one of the two factors.
• In homozygous parents, all gametes produced are similar; while in heterozygous parents, two kinds of gametes are produced in equal proportions.