Genetic Cross in Drosophila Melanogaster: Understanding Crossover Events
What phenotypic classes of offspring result from a crossover event in Drosophila melanogaster?
The genes for miniature wings (m) and garnet eyes (g) are approximately 8 map units apart on chromosome 1 in Drosophila. Phenotypically wild-type females (m + g / mg +) were mated to miniature-winged males with garnet eyes. Which of the following phenotypic classes reflect offspring that were generated as a result of a crossover event? 1) miniature wings, garnet eyes 2) garnet eyes 3) miniature wings 4) wild type Final answer:
Answer:
In the genetic cross involving Drosophila melanogaster, the phenotypic classes of offspring that result from a crossover event between the genes for miniature wings and garnet eyes are miniature wings with wild-type eyes and wild-type wings with garnet eyes.
The question is asking about a genetic cross involving Drosophila melanogaster, specifically concerning genes for miniature wings and garnet eyes. These genes are located 8 map units apart on chromosome 1. A wild-type female, heterozygous for both the miniature wing (m+) and garnet eye (g+) traits, was mated with a male that has the miniature wing and garnet eye phenotypes. In terms of the offspring resulting from a crossover event, the two phenotypic classes that would indicate a crossover are miniature wings with wild-type eyes and wild-type wings with garnet eyes. This is because a crossover would result in recombination of the linked genes, producing new allele combinations.
Genetic crosses in Drosophila melanogaster are important for understanding genetic inheritance patterns and gene mapping. The phenomenon of crossover events, which result in recombination of linked genes, is a crucial aspect of genetic studies in this model organism. By studying the phenotypic classes of offspring resulting from such events, researchers can gain insights into the process of genetic recombination and the linkage of genes on chromosomes.