• When two pairs of contrasting alleles present in parents inherit to offspring, one pair of alleles is independent to other pair.
• They don’t remain linked and sort randomly.
• Eg: When a pea plant of two different characters round and yellow seed and green and wrinkled seed are crossed then in F1 generation, all plants are round and yellow seed but in F2 generation , plant show four types of characters in ration 9:3:3:1.

Here, cross between yellow and round seed (YYRR) and green and wrinkled seed(yyrr) is given below:

• Genotypic ration: 1:2:2:4:1:2:1:2:1
• Phenotypic ratio: 9:3:3:1