Filial crossing of the Dumpy Sepia Dihybrid Mutation in Drosophila Melanogaster does not follow Mendel’s ideal Ratio and The Law of Independent Assortment. Abstract A genetic cross was performed on the Drosophila Melanogaster fruit fly in order to observe the occurrence of transmission genetics in its phenotypic results. The experiment also aimed to determine whether these flies follow Mendel’s Laws of Segregation and Independent Assortment. Wild type female fruit flies were crossed with Dumpy Sepia male flies in order to test the laws of heredity. After two filial crosses the flies of the F2 generation were counted and separated according to their phenotypes. A Chi-square statistical test was then performed on the results of the cross and …show more content…
We then selected four males and four females and placed the back into a clean vial and discarded any remaining flies. Once we ensured that all these flies were still alive, we transferred the into the fresh culture bottle that was provided for us. We then labelled our fresh culture bottle and returned it to the baskets for incubation. Next we examined some of the left over flies and recorded the phenotypes of the F1 generation. Week 4 The F1 generation flies had mated and laid eggs and the offspring were in the larval stage. We discard the parental generation using ether, so that they would not interfere with the analysis of the F2 generation in Week 5. Next we shook all the flies from our culture jar into our etherising jar, ensuring that we removed all the adult flies, and returned our jar for incubation. Week 5 As it was our final experiment for this task we began by moistening the lid of our etherising jar with ether and emptied all our flies from the cross into the jar, ensuring that none escaped. We the separated the flies into their various phenotypic classes and counted the number of flies in each group. We then recorded our results. We used a punnet square to establish our expected phenotypic ratios for the Dumpy Sepia and Wild type cross. We then used a Chi-square test to determine whether our individual results as well as the class’s results differed significantly from the expected phenotypic ratios of Mendelian