Explain Mendel's Law of Independent Assortment with the help of a dihybrid cross. Also, write down the phenotypic and genotypic ratios obtained in the F2 generation.

Q: Explain Mendel's Law of Independent Assortment with the help of a dihybrid cross. Also, write down the phenotypic and genotypic ratios obtained in the F2 generation.

Introduction to the Law of Independent Assortment\nMendel's Law of Independent Assortment is the third major principle of inheritance formulated by Gregor Johann Mendel. This law states that when two pairs of traits are combined in a hybrid, segregation of one pair of characters is independent of the other pair of characters at the time of gamete formation. In simpler terms, the alleles of two or more different genes get sorted into gametes independently of one another. The inheritance of one gene does not affect the inheritance of another gene. Explanation through Dihybrid Cross\nTo demonstrate this law, Mendel crossed a pea plant having yellow and round seeds (YYRR) with a pea plant having green and wrinkled seeds (yyrr). Parent Generation (P): Yellow Round (YYRR) × Green Wrinkled (yyrr) Gametes produced by parents: YR and yr F1 Generation: All offspring were heterozygous for both traits (YyRr) and showed the yellow and round phenotype. \nWhen the F1 generation plants (YyRr) were self-pollinated, they produced four types of gametes in equal proportions: YR, Yr, yR, and yr. \nUsing a Punnett square (Checkerboard) for the F2 generation, 16 possible combinations are formed: Yellow Round (YYRR, YYRr, YyRR, YyRr): 9 plants Yellow Wrinkled (YYrr, Yyrr): 3 plants Green Round (yyRR, yyRr): 3 plants Green Wrinkled (yyrr): 1 plant F2 Generation Ratios Phenotypic Ratio: 9 : 3 : 3 : 1 (9 Yellow Round : 3 Yellow Wrinkled : 3 Green Round : 1 Green Wrinkled) Genotypic Ratio: 1 : 2 : 1 : 2 : 4 : 2 : 1 : 2 : 1 (Detailed as YYRR:2YYRr:1YYrr:2YyRR:4YyRr:2Yyrr:1yyRR:2yyRr:1yyrr) Conclusion\nThe appearance of new combinations like Yellow Wrinkled and Green Round in the F2 generation clearly proves that the factors (genes) for seed color and seed shape assort independently of each other during gamete formation.

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Introduction to the Law of Independent Assortment
Mendel's Law of Independent Assortment is the third major principle of inheritance formulated by Gregor Johann Mendel. This law states that when two pairs of traits are combined in a hybrid, segregation of one pair of characters is independent of the other pair of characters at the time of gamete formation. In simpler terms, the alleles of two or more different genes get sorted into gametes independently of one another. The inheritance of one gene does not affect the inheritance of another gene. Explanation through Dihybrid Cross
To demonstrate this law, Mendel crossed a pea plant having yellow and round seeds (YYRR) with a pea plant having green and wrinkled seeds (yyrr). Parent Generation (P): Yellow Round (YYRR) × Green Wrinkled (yyrr) Gametes produced by parents: YR and yr F1 Generation: All offspring were heterozygous for both traits (YyRr) and showed the yellow and round phenotype. 
When the F1 generation plants (YyRr) were self-pollinated, they produced four types of gametes in equal proportions: YR, Yr, yR, and yr. 
Using a Punnett square (Checkerboard) for the F2 generation, 16 possible combinations are formed: Yellow Round (YYRR, YYRr, YyRR, YyRr): 9 plants Yellow Wrinkled (YYrr, Yyrr): 3 plants Green Round (yyRR, yyRr): 3 plants Green Wrinkled (yyrr): 1 plant F2 Generation Ratios Phenotypic Ratio: 9 : 3 : 3 : 1 (9 Yellow Round : 3 Yellow Wrinkled : 3 Green Round : 1 Green Wrinkled) Genotypic Ratio: 1 : 2 : 1 : 2 : 4 : 2 : 1 : 2 : 1 (Detailed as YYRR:2YYRr:1YYrr:2YyRR:4YyRr:2Yyrr:1yyRR:2yyRr:1yyrr) Conclusion
The appearance of new combinations like Yellow Wrinkled and Green Round in the F2 generation clearly proves that the factors (genes) for seed color and seed shape assort independently of each other during gamete formation.

MP Board · Class 12 · Biology · Principles of Inheritance and VariationExplain Mendel's Law of Independent Assortment with the help of a dihybrid cross. Also, write down the phenotypic and genotypic ratios obtained in the F2 generation.

Explanation through Dihybrid Cross\nTo demonstrate this law, Mendel crossed a pea plant having yellow and round seeds (YYRR) with a pea plant having green and wrinkled seeds (yyrr).

F2 Generation Ratios

Conclusion\nThe appearance of new combinations like Yellow Wrinkled and Green Round in the F2 generation clearly proves that the factors (genes) for seed color and seed shape assort independently of each other during gamete formation.