In addition to wild-type flies, 29 different mutations of the common fruit fly, Drosophila melanogaster, are included in FlyLab. The 29 mutations are actual known mutations in Drosophila. These mutations create phenotypic changes in bristle shape, body color, antennae shape, eye color, eye shape, wing size, wing shape, wing vein structure, and wing angle. For the purposes of the simulation, genetic inheritance in FlyLab follows Mendelian principles of complete dominance. Examples of incomplete dominance are not demonstrated with this simulation. A table of the mutant phenotypes available in FlyLab can be viewed by clicking on the Genetic Abbreviations tab which appears at the top of the FlyLab homepage. When you select a particular phenotype, you are not provided with any information about the dominance or recessiveness of each mutation. FlyLab will select a fly that is homozygous for the particular mutation that you choose, unless a mutation is lethal in the homozygous condition in which case the fly chosen will be heterozygous. Two of your challenges will be to determine the zygosity of each fly in your cross and to determine the effects of each allele by analyzing the offspring from your…
25.) When Thomas Hunt Morgan crossed his red-eyed F1 generation flies to each other, the F2 generation included both red and white-eyed flies. Remarkably, all the white-eyed flies were male. What was the explanation for this result?…
1. In fruit flies, long wings are dominant to short wings. Complete a cross between a short winged male and a heterozygous female.…
In the reciprocal cross, the behavioural phenotypes were isolated from one another while the wing veins were kept constant (in this case both wild type). When the wild type mellow female Drosophila and wild type hyper male Drosophila were crossed, all female offspring obtained a similar phenotype to that of the male parental while all the male offspring had phenotypical combinations similar to that of the female parent. This set of results shows that the mellow behavioral phenotype is a recessive x-linked gene carried by the female because the resulting male offspring showed the same characteristics to that of the female parent (received X – chromosome from female parent). On an additional note, there was a higher frequency of females in comparison to men; 121 and 105 respectively. In addition, the behavioral gene is sex -linked also because of the different resulting phenotypical ratio in comparison to the cross carried out in vial one.…
This lab was the study of monohybrid as well as dihybrid crosses. A monohybrid cross is the study of a certain trait whereas a dihybrid cross is the study of the mating experiment between two organisms that are identically hybrid for two traits. ( Reference 1 ) This lab was done to determine the genetic mutations after each generation and to observe the ratios. As each generation of fruit flies came to existence, traits would either be different from each fly or certain traits would disappear from existence. The expected ratio for a monohybrid cross was 3:1 and 9:3:3:1 for the dihybrid cross. For the monohybrid cross, eye color was observed to be wildtype, dark red, or white eyed, which was x-linked. (Reference 2) As for the dihybrid cross, both wing shape as well as eye color was observed. The wings were either straight, wildtype, or shriveled, vestigial, depending on…
The goal of the Drosophila melanogaster lab was to breed homozygous wild-type Drosophila melanogaster with homozygous mutant Drosophila…
The class was given vials with adult fruit flies of P1 parent generation to look at the traits, one generation was homozygous, wild type eyes and dumpy wings. The other one was homozygous for sepia eyes and normal wings. These were crossed to yield the F1 generation which is crossed to produce the F2 generation.…
Mendel also performed experiments looking at inheritance patterns of two traits together. From this he formulated the law of independent assortment. A test cross can also be performed to discover if individuals expressing the dominant allele are homozygous or heterozygous. Geneticists today often use Drosophila melanogaster as a test subject. The wild type fruit fly is used to discover inheritance patterns in mutant flies.…
This experiment focuses specifically on Drosophila melanogaster, also known as the common fruit fly (Lynch, M., et al. pp 645-663). For over 100 years scientists have been using them in experiments as they are referred to as a “model organism.” They were deemed a “model organism” since they are characterized as…
Gregor Mendel created 3 principles as it relates to the laws of genetics. The 3 principles of Mendel’s laws of genetics are the law of dominance, the law of segregation and the law of independent assortment. The law of dominance stated that in a heterozygous condition, the dominant allele will dominate over another allele. This means that the dominant trait or phenotype will be present. The law of segregation states that for any trait or phenotype, the parent alleles will separate and only one allele from each parent will pass to the offspring. (O’Neil, 2011) The law of independent assortment states that different pairs of alleles are passed to each other independently. (O’Neil, 2011) Because of Mendel’s laws, D. melanogaster, is the organism often studied for genetics research. Some of the reason for studying the flies genetically is because they are small and easy to grow in a lab setting. They have a 2 week life cycle and a new generation can be…
Drosophila melanogaster or more commonly referred to as “fruit flies” have been used for genetic research for over 100 years. During his time at Harvard university, Charles W. Woodworth is credited with being the first to suggest fruit flies be used for genetic research. A century later, fruit flies are the most widely used eukaryotic organism for genetic research (Drosophila). Their ease of use and rapid rate of reproduction has allowed researchers across the globe further our knowledge of genetics.…
They thought Mendel’s hereditary determinants were on a locus. They found out that the physical separation of alleles during anaphase I of meiosis accounts for Mendel’s principle of segregation. If the alleles for different genes are located on different chromosomes, they assort independently from one another in meiosis I. This confirmed the principle of independent assortment. Later on, the two scientists came up with the chromosome theory of inheritance, which states that independent assortment happens in metaphase and anaphase of meiosis I. To test the theory of inheritance, scientist Thomas Hunt Morgan used the fruit fly. At one point, Morgan noticed that a male fruit fly had white eyes rather than the wild type red eyes. He concluded that the white eyes resulted from a mutation. He mated a red-eyed female with a mutant white-eyed male and the results showed that all of the F_1 females had red eyes, but the F_1 males had white eyes. This was very peculiar because Mendel already proved that traits are not sex based. Morgan realized that the X chromosome in males and females explained his results. He determined that eye color is carried on the X chromosome and not on the Y chromosome. This is described as sex-linked inheritance. According to the X-linkage hypothesis, a female has two copies of the eye color gene because they have the two X chromosomes, whereas the male fruit flies have the one X chromosome that codes for eye color. The reciprocal cross of pea plants happened on non-sex chromosomes called autosomes. Genes on non-sex chromosomes show autosomal inheritance. Biologists now know that Boveri’s and Sutton's chromosome theory of inheritance was…
These flies were observed in the lab by anaesthetizing them with triethylamine so they won’t fly away. They were then inserted in a vial with a foam stopper so then it was easier to observe them. A dissecting microscope was used to identify the color of their bodies, wing shape, sex characteristics, and any other body characteristics. We used female fruit flies who were virgins six hours after they came out of their cocoons and mated them with male fruit flies. This is how crosses were made while there were a few Genetic…
in this experiment the number of ebony flies were double the number of wild type flies, but they were put in a similar condition to our experiment (Salata, et al., 2002). The observed gene frequency of the two types of flies very close to the expected gene frequency over the 12 weeks’ period. The number of ebony type flies experienced a gradual decrease, but this was expected from the formula because heterozygous flies were yield by the mating of the homozygous wild type with a homozygous recessive type flies. The results of this experiment also showed no evolution (Salata, et al., 2002).…
In order to begin the experiment, culture vials for the flies were created. After wearing the proper safety gear, including but not limited to gloves and a lab coat, the fly food source was made using roughly an equal amount of distilled water and fly food. These were mixed until it had a mashed potato-like consistency. It mustn’t be too liquid-like as it will kill the flies; and should be solid enough to not slide around the vial. After obtaining and labelling a new vial, the food mash was placed inside, filling about one inch of the vial. Any excess food that was not at the bottom was cleaned off. Fly netting was placed as a U-shaped, with the bottom of the U barely touching the food. The netting was used to allow the larvae an area to prepare…