Fruit Fly Lab

4. Clear wing, Black eye, and Hairless (c, b, and h) are linked, recessive traits carried on

This may have been the cause of the low numbers of white lozenge in the F2 generation of flies. However, the cause of white eyes is a defective red pigment gene and should not affect the vision of the flies, whereas the lozenge gene should have a greater affect due to it causing the malformation of the fly's eyes. Therefore the lozenge flies should have also been in lower than expected numbers, but it was found that they were actually in higher than expected numbers making the validity of this argument questionable.

The parents are both homozygous. The homozygous dominant would represent the wild type. And the homozygous recessive would represent the other fly parent of a different strain. The F1 generation would consist of 100% Wild Type but they would all be heterozygous in carrying the recessive gene.

To set up this experiment, two twenty-five gallon aquariums, 3 petri-dishes, 200 flies, rotten bananas, and yeast were used. The bananas chosen to be an accelerant for the growth of the yeast and were frozen so they would be easier to cut. The yeast was used because the drosophila melanogaster prefer this as a food source.  The vestigial and wild type flies were sexed (to determine their sex), sorted, and counted.  An initial population size of 100 total flies was decided so that it would be easier to determine the phenotypic percentage of the total population. Fly paper was placed in one of the sets of cages to impose a method of natural selection as well as the sexual selection which is being solely tested by the other set of cages.

Introduction: The intention of this lab was to gain a better understanding of Mendelian genetics and inheritance patterns of the drosophila fruit fly. This was tasked through inspecting phenotypes present in the dihybrid crosses performed on the flies. An experimental virtual fly lab assignment was also used to analyze the inheritance patterns. Specifically, the purpose of our drosophila crosses is to establish which phenotypes are dominant/recessive, if the traits are inherited through autosome or sex chromosomes and whether independent assortment or linkage is responsible for the expressed traits.

The conducted experiment assists in determining an unknown mutant allele found in Drosophila melanogatser. Mutant 489 illustrates a defect in eye pigmentation, which displays a dark brown eye color verses the brick red eyes in wild type flies. Based on the appearance our 489 mutation we've names our mutant rust.

The expected number of wild type flies in the F2 generation is 734.25 and the expected number of shaven bristle flies in the F2 generation is 244.75. This, again, exhibits a 3:1 ratio of normal phenotype to affected phenotype.

Describe the sex and phenotype of the mutant fly. Describe the phenotype as it compares to the wild type.

There were eight different phenotypes among the progeny. The highest phenotypic frequency was the w+m+f+ at 40% of the progeny. The lowest was the w+mf+ with only 2 % of the progeny (Table 3). The sum of the recombinant frequencies between genes, table 4, was used to determine the gene distance. The recombinant frequency was determined by counting the number of individuals whose genes differed from that of the parental type. For example, how many individuals white eye gene, and miniature wing gene, differed from both wild-type or both mutants. Recombination occurred between the white and miniature gene 33 times. Recombination occurred between the miniature and the forked genes 31 times. Recombination occurred between the white and forked genes 44 time. Double recombination occurred 10 times. Therefore, genes w and f are 64 m.u. apart, m and w are 33 m.u. apart, and m and f are 31 m.u. apart (Figure

Heterozygotes, which have the wild type phenotype, have normal sight which gives them the advantage of finding a mate and have a better success with attracting a mate with their courtship song (Kyriacou et al, 1978). The male heterozygous Drosophila had a better advantage at mating than the homozygotes, which were the ebony, and therefore we predict there will be more wild type by the end of the experiment.

Introduction Drosphila melanogaster, commonly known as the fruit fly, is an excellent organism for genetics studies because it has simple food requirements, occupies little space, is robust, completes its life cycle in about 12 days at room temperature, produces large numbers of offspring, can be immobilized readily for examination and sorting, and has many types of hereditary variations that can be observed with low-power magnification. The fruit fly has a small number of chromosomes (4 pairs), which are easily located in the large salivary gland cells. As mentioned before, the fruit fly life cycle is complete in about 12 days. First, a fertilized adult female must lay the egg, which leads to the first stage of the fruit fly life cycle, the egg stage.

Introduction Have you ever wondered how specific traits are passed down from generation to generation? Or if you already know the answer to that question, then how can you determine which traits are dominant and recessive. Finding both answers can be obtained by studying genetics. Reading about these topics only gives you a grasp on how traits work. In a laboratory setting, the answers can be found in an experiment using an unlikely specimen, known as the common fruit fly and its scientific name, Drosophila Melanogaster.

we said goodbye and placed them in the fly morgue. We allowed the F2 larval

If mutations occurred, the flies would be sepia (brown eyes) and apterous (no wings).

This experiment looks at the relationship between genes, generations of a population and if genes are carried from one generation to another. By studying Drosophila melanogaster, starting with a parent group we crossed a variety of flies and observe the characteristics of the F1 generation. We then concluded that sex-linked genes and autosomal genes could indeed be traced through from the parent generation to the F1 generation.