In a series of crosses between two true-breeding strains of peaches, the F₁ generation was uniform, producing 30-g peaches. The F₂ fruit mass ranges from 38 to 22 g at intervals of 2 g. Using gene symbols of your choice, give the genotypes of the parents and the F₂.

Key Concepts

True-breeding Strains

True-breeding strains are organisms that, when mated, produce offspring that are identical to themselves for specific traits. In genetics, this means that the parents are homozygous for the traits being studied, ensuring that the F₁ generation will display a uniform phenotype, as seen in the 30-g peaches.

F₁ and F₂ Generations

The F₁ generation is the first filial generation resulting from a cross between two true-breeding parents. In this case, the F₁ peaches are uniform at 30 g. The F₂ generation arises from self-fertilizing the F₁ individuals, leading to a phenotypic range, as observed with fruit masses ranging from 22 g to 38 g.

Phenotypic Variation and Gene Symbols

Phenotypic variation refers to the observable differences in traits among individuals, which can be attributed to genetic and environmental factors. In this scenario, the range of peach weights in the F₂ generation suggests multiple alleles at play. Gene symbols can be assigned to represent these alleles, helping to illustrate the inheritance patterns and genotypes of the parents and offspring.