Introduction: The Drosophila melanogaster, otherwise known as the common fruit fly has been a useful organism to the field of genetics. It has a relatively short generation time of approximately 10 days at 25 degrees Celsius, and yields a large amount of offspring. This results in large amounts of data over a short time period. In this lab, the purpose was to demonstrate how the Drosophila melanogaster is used in the field of genetics to study the inheritance of traits throughout the F1 and F2 generations. Drosophila melanogaster was introduced into the wild type and other mutant alleles such as white eyed, vestigial, and sepia. The results gathered in the lab would then be compared to actual results, and a Chi-Square test will be used for
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Crossing over is the exchange of genetic material between homologous chromosomes that will result in recombinant chromosomes. The crossing over occurs when homologous chromatids in the tetrad, one from each parent, exchange segments of a varying length during the process of prophase. The point of crossing over is known as the chiasma. Usually, there is crossing over which will occur between genes that lies on the same chromosome which will result in a new combination of traits. If the traits are linked and lie to close to together on the chromosome they cannot cross over (National Health Museum). Due to each crossing over only leading to half recombination gametes, half nonrecombinant gametes, the total percentage of recombinant gametes is always half of the percentage, so the maximum proportion of recombinant gametes is always 50%.
Chromosome Mapping: Chromosome mapping in Drosophila melanogaster is a powerful tool for analyzing the function of specific genes. The chromosome mapping can be used to identify the location of specific genes on the genome. The recombinant frequency is constant for any pair of linked loci which represents the genetic map distance. By using the frequencies of single and double crossovers we can create a chromosome mapping that will show the genome of the fruit fly. These chromosome maps are measured in map units or centiMorgans.
Crossing over is the exchange of genetic material between homologous chromosomes that will result in recombinant chromosomes. The crossing over occurs when homologous chromatids in the tetrad, one from each parent, exchange segments of a varying length during the process of prophase. The point of crossing over is known as the chiasma. Usually, there is crossing over which will occur between genes that lies on the same chromosome which will result in a new combination of traits. If the traits are linked and lie to close to together on the chromosome they cannot cross over (National Health Museum). Due to each crossing over only leading to half recombination gametes, half nonrecombinant gametes, the total percentage of recombinant gametes is always half of the percentage, so the maximum proportion of recombinant gametes is always 50%.
Chromosome Mapping: Chromosome mapping in Drosophila melanogaster is a powerful tool for analyzing the function of specific genes. The chromosome mapping can be used to identify the location of specific genes on the genome. The recombinant frequency is constant for any pair of linked loci which represents the genetic map distance. By using the frequencies of single and double crossovers we can create a chromosome mapping that will show the genome of the fruit fly. These chromosome maps are measured in map units or centiMorgans.