The Relationship Between Phenotypes and Genotypes in the F2 Generation

For n = number of genes independently segregating, how many different phenotypes and genotypes are observed in the F2 generation? Assume complete dominance at each gene.

The number of different phenotypes in the F2 generation for n independently segregating genes with complete dominance is 2^n, and the genotypes is 3^n. The correct answer is A. Phenotypes: 2^n, Genotypes: 3^n

Explanation:

Phenotypes: In the F2 generation, the number of different phenotypes observed is determined by the number of genes independently segregating. For each gene, there are two potential phenotypic outcomes - dominant or recessive. Therefore, with complete dominance at each gene, the total number of different phenotypes is calculated as 2^n. Genotypes: Similarly, the number of different genotypes observed in the F2 generation is also influenced by the number of independently segregating genes. Since there are three possible combinations for each gene - homozygous dominant, heterozygous, and homozygous recessive - the total number of different genotypes can be expressed as 3^n. Therefore, in the F2 generation with n independently segregating genes exhibiting complete dominance, the number of different phenotypes is 2^n and the number of different genotypes is 3^n. This relationship highlights the influence of genetic inheritance and dominance on the variation observed in offspring generations.
← The intriguing genetics of honeybees The impact of deforestation on biodiversity →