A wild-type male and a wild-type female Drosophila with red eyes and full wings are crossed. Their progeny are shown below.

Males                                       Females                          _
3/8 full wing, red eye                 3/4 full wing, red eye
3/8 miniature wing, red eye.      1/4 purple eye, full wing
1/8 purple eye, full wing
1/8 miniature wing, purple eye

Using clearly defined allele symbols of your choice, give the genotype of each parent.

Key Concepts

Drosophila Genetics

Drosophila melanogaster, commonly known as fruit flies, are a model organism in genetics due to their simple genetic structure and short life cycle. They have well-defined phenotypes, such as eye color and wing size, which are controlled by specific genes. Understanding the inheritance patterns of these traits is crucial for analyzing genetic crosses and predicting progeny outcomes.

Alleles and Genotypes

Alleles are different versions of a gene that can exist at a specific locus on a chromosome. In this context, the traits of eye color and wing size in Drosophila are determined by alleles, which can be dominant or recessive. The genotype refers to the specific alleles an organism possesses, which can be represented using symbols (e.g., 'w+' for wild-type red eyes and 'w' for purple eyes).

Punnett Squares and Phenotypic Ratios

Punnett squares are a tool used to predict the genotypic and phenotypic ratios of offspring from a genetic cross. By analyzing the combinations of alleles from the parents, one can determine the expected ratios of traits in the progeny. In this case, the ratios of full and miniature wings, as well as red and purple eyes, can be calculated to infer the genotypes of the wild-type parents.