Mendel 's Two Laws Help Us Understand And Analyze Genetic Crossings

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When trying to understand genetics Mendel 's laws are a very big part of it. Mendel 's two laws help us understand and analyze genetic crossings. In our experiment we used drosophila melanogaster flies, a common fruit fly. This was perfect to understand and visualize how the laws take effect. Mendel stated that during the process of genetic crossing; two alleles are formed which then separated to form gametes, which would appear in fertilization. In our experiment we accomplish a cross that determined different eye and body colors. By using the Chi-Square test, we were able to test our results. Our groups hypothesis stated the number of flies from the F2 generation would accommodate Mendelian Genetic Ratio of 9:3:3:1. Our Chi-Square test results did not correspond with Mendelian Ratio, which meant we would need to reject our hypothesis. Introduction In the 19th century Gregor Mendel accomplished pioneered the first laws of genetics after crossing peas. He conducted an experiment with pea plants. He would use a paintbrush to transfer the genetic coding from one pea plant to another, so he could know exactly who the parents were. With the end of this experiment Mendel came up with two laws; Mendel 's law of segregation, and Mendel 's law of independent assortment. Mendel crossed over purple pea flowers with white pea flowers, which gave him purple pea flowers for the first generation also called F1. Since the offspring were all purple flowers Mendel understood that the purple gene was the dominant gene. Mendel decided to cross the F1 generation with themselves. Which resulted in three purple pea flowers and one white pea flower. By using basic Punnett square, and identify the genotype as PP and the phenotype as pp. This gave Men... ... middle of paper ... ...ld reject the null hypothesis and accept the alternative hypothesis. This means that our hypotheses which we predicted to have a ratio of 9:3:3:1 was incorrect this would have happened for a number of reasons. For cross A our ratio was 6:2:6:2, and for cross B it was 9:3:3:1 which is closer to Mendel’s ratio. The reason that out ratios do not match up to Mendel’s ratio would have been the following. While gathering our data for the flies, some flies dies in the process of mating. While we were gathering out data to use for the Chi-table we did not receive the correct data. Another reason for such an abnormal ratio would have been because the parental generation mated with the offspring’s because we did not cross the virgin flies. Finally, while we were crossing over the flies from one generation to another we did not cross over the correct number of male to female.

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