Genetics 382 Lab Report

In this experiment we tested to see what the offspring of an unknown cross of an F1 generation would produce. After observing the F2 generation and recording the data we found some of the Drosophila showed mutations, two in particular. The mutations were the apterus wings, and sepia eyes. After collecting our data through observation, a Chi-test was conducted resulting in a Chi-value of 5.1 and a p-value of .2. Since the p-value was greater than 0.05, there was no significant change in the data. This proved that the Drosophila flies still followed the Mendelian genetics of a 9:3:3:1 ratio.

A) Their F1 offspring were 97 wild type quahaug flies. What is the genotype of these F1 flies??

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.

The null hypothesis is rejected since the p-value is below the significance level of 0.05.

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.

melanogaster, leaving B and D to be our mutants. Before crossing our populations, we made not of each one’s phenotype in order to see how crossing them would affect their phenotypes: Population B flies had no wings and red eyes, population D had full wings and black eyes and population G had full wings and red eyes. We expected the resulting phenotypes to be some sort of combination, revealing which traits were dominant. However, what we did not expect was the abnormal mutant that arose in a couple of our populations.

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

Table 1 shows the phenotypes of the F1 flies produced by crossing P1 wild-type females and P1 no-winged mutant males. The results of that cross was that there were forty seven wild-type females and fifty three wild-type males. Therefore there was a total of one hundred wild-type flies that were produced. The observed phenotypic ratio of wild-type flies and no-winged mutant flies was 1:0 (wild-type: no-winged). The predicted phenotypic ratio if the no-winged mutation is autosomal recessive would be 1:0 (winged: no-winged).

The degree of freedoms was 9 and the significance level was 0.05. For these conditions, the chi-square value must be above 16.92. The test statistic provided no convincing evidence that the

Purpose The purpose of this experiment is to determine whether the fruit flies were dominant/recessive or linked/non-linked. The traits I chose for this activity was the fruit fly with vestigial wings and purple eyes, the other fruit fly I chose was a normal fly, also called wild type. While writing out my plan for this activity I thought it would be interesting to test a female mutant and the wild type male, the ratios I came up for this experiment was 2:2 and the mutant allele being recessive to the wild type. In this case, the words recessive and dominant means, if the child born from the parents inherits more of the genes and traits from let us say the father then the alleles of the father is dominant over the mother’s genes.

Fruit Fly experiment was conducted by using different techniques. One of the main things was to examine the fruit flies and identify the difference between females and males, identify their mutation if they were wild type, white eye, vestigial or white and vestigial combined together. These Fruit flies were kept in the incubator at 25°C for about 6 days. The main goal for this experiment was to observe the principles of Mendelian genetics.

* The p-value= 0.282. The p-value is another complementary and equally valid way we can evaluate the null and alternative hypotheses is by looking at the p-value and compare the p-value to alpha. If the p-value is less than alpha, reject the null hypothesis and accept the alternative

D., Liang, J. O., Pickart, M. A., Pierret, C., & Tomasciewicz, H. G., 2012). In relation to genetics, the goal of this experiment was to use Glofish to carry out an analysis of Mendelian inheritance patterns. The experiment consisted of characterizing several groups of adult progeny containing wildtype and transgenic fish. First, each phenotype of the progeny was counted, a hypothesis was generated about the inheritance patterns of each trait, and then the hypotheses were tested using chi-square statistical analysis. Based on the inheritance, major results and conclusions were drawn from the observations and data collected during the

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.