Mendel's Law Of Genetic Analysis

In order to be able to determine whether the drosophila Melanogaster fly cross will follow Mendel’s law of Independent assortment in a 9:3:3:1 phenotypic ratio a dihybrid cross was performed of cinnabar brown flies with wild type flies. It was observed that the mutant phenotypes became visible in the second filial generation, thus following the law of independent assortment in the first filial generation. It was also concluded that in the first filial generation the dominant genotypes masked the phenotypic effects of the recessive genotypes and the dominant genotypes were expressed phenotypically, namely all had bright red eyes. However the Chi-square test calculations resulted in the rejection of the null hypothesis in both the case of the small group and entire class. Thus the results showed a …show more content…
Through his examination of the dihybrid cross in breeding of pea plants Mendel formulated from his observations a 9:3:3:1 ratio of phenotypic traits in the second filial generation. Thus he formulated the law of independent assortment which will be examined in this experiment. This law states that alleles for different genes separate independently during gamete formation (Reece et al., 2011).
The Drosophila Melanogaster is the organism used to study Mendel’s proposed patterns of inheritance because of its obvious advantages in that it is small and easy to contain and breed in a laboratory; it contains physical traits known as phenotypes that are easy to identify and it produces large numbers of offspring in a short amount of time (Turnpenny and Ellard, 2012).
The aim of this experiment if to test Mendel’s law of independent assortment though the dihybrid cross of cinnabar brown females (cn/cn;bw/bw) with wild type males (cn+/cn+;bw+bw+) where a 9:3:3:1 ratio is