Question

What is the Law of Independent Assortment? Explain with an example?

Answer 1

Law of Independent Assortment :

1. It has been called Mendel's Second Law by Correns.
2. According to this law, the alleles of two pairs of traits separate independently of each other during gamete or spore formation and get randomly rearranged in the offspring at the time of fertilization, producing both parental and new combinations of traits.
3. There is occurrence of two important events. First is separation of the alleles of two pairs of traits independently of each other during gamete or spore formation. Second is rearrangement of alleles (random union of alleles) in the offspring at the time of fertilization.
4. This law can be explained with the help of dihybrid cross.

Example of dihybrid cross:

A cross is made between a pure round yellow seeded pea plant (RRYY) with wrinkled green seeded pea plant (rryy). Yellow colour is dominant over green and rounded seed shape over wrinkled seed shape. F₁ plants (hybrid plants) are all round and yellow seeded. F₁ plants are allowed to self breed and produce F₂ generation. F₂ generation has four types of plants rounded yellow, rounded green, wrinkled yellow and wrinkled green in the ratio of 9:3:3 1. Each of the character if considered seperately shows a ratio of 3:1 as found in monohybrid cross.