Drosophila Melanogaster Lab Experiment

Butterflies have many genes which are expressed into ways that are either dominant, or recessive. For example to have blue eyes the dominant allele would be (B) and the recessive allele would be (b).

For one of the monohybrid crosses you performed in this Investigation, describe how to use the phenotype ratios to determine

Suppose the feather color of a bird is controlled by two alleles, D and d. The D allele results in dark feathers, while the d allele results in lighter feathers.

Apply your understanding of how alleles assort and combine during reproduction to evaluate a scenario involving a monohybrid cross.

It was decided that there would be 80 vestigial flies and 20 wild type flies to total to an initial population of 100 drosophila. Next, the flies were anesthetized flies using Fly Nap. The flies were counted out to reach desired ratio, sexing the flies making sure there are equal amounts of males and females to be sure there is ample individuals to allow successful mating. The fly’s food was prepared by taking a frozen rotten banana, cutting it in half, mashing up the banana meat, and mixing yeast into it. The

Drosophila Melanogaster, commonly known as fruit flies, are highly important model organisms in pertaining to biological research. The logic behind their recurrent use is due to their: easy culture in the laboratory, brief generation time, and ability to produce large numbers of offspring. In this report, we created isolated virgin D. Melanogaster from the original three populations we were given and then created crosses between them. Upon observation, we noticed an unusual mutant that arose from two of the three created crosses. We suspected that this genetic mutation had previously been discovered and named.

It would be expected that the mutant F1 flies would be heterozygous for the allele responsible for the grounded trait. If two F1 flies were mated, the percentage of flies that would be expected to be wildtype in the F2 generation would be 25% mutants given that the mutant allele (ap) is predicted to be recessive and, leaving 75% to be wildtype (ap+).

Jack J, DeLotto Y. Effect of Wing Scalloping Mutations on Cut Expression and Sense Organ Differentiation in the Drosophila Wing Margin. Genetics. 1992;131(2):353-363.

11. The progeny of a Drosophila female (heterozygous at three loci: y, ct, and w) crossed to a wild type male are listed below:

but homozygous recessive for seed color (Ttyy). If 80 offspring are produced, how many are expected to be

METHODS: In this experiment, the instructor provided us with 30 ebony individuals and 20 wild type individuals. In order to get an exact amount of each type, we anesthetized the flies and counted them off by gently using a fine point paint brush. Then all 50 Drosophila were put into a population cage which had a lid that had six holes for the centrifuge tubes. Two food tubes and four clean, empty tubes were added on the first day. Each food tube consisted of half a cup full of food mixed with 6-7 milliliters of water. This was the fly medium. The food should turn blue once the water is added. Each tube was labeled with a number and with the date. Every two to three days we added one more food tube until all 6 tubes contained the fly medium. After all 6 tubes were filled, the following days after we exchanged the first food tube with a new food tube. At the end of the experiment, we fed the flies with a total of 8 food tubes. Then the flies were anesthetized, again. At the end of this four week lab, the number of living ebony and wild

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

Based on your results for the female offspring, predict whether color blindness is a dominant or recessive trait. Explain your reasoning.

For our first generation (F1) of flies we chose to cross apterous (+) females and white-eye (w) males. We predicted that the mutation would be sex linked recessive. So if the female was the sex with the mutation then all females would be wild type heterozygous. Heterozygous is a term used when the two genes for a trait are opposite. The males would all be white eye since they only have one X chromosome. If the males were the sex that had the mutation then all the flies would be wild type but the females would be heterozygous.

The pairs of alternative traits examined segregated among the progeny of a particular cross, some individuals exhibiting one traits, some the other