...INTRODUCTION The fruit fly, Drosophila melanogaster, was used as a model organism to study the law of segregation and the law of independent assortment in Mendelian genetics. Drosophila was chosen as our model organism not only because of its short life cycle and fast breeding time but also because they are easy to maintain and handle in the laboratory. In this experiment a monohybrid cross and a dihybrid cross were performed. The law of segregation establishes the concept of dominance. The law of segregation states that an individual organism possesses two alleles that can encode a trait and that these alleles separate when gametes are formed and one of the two alleles go into each gamete. The concept of dominance states that when two alleles that encode for a trait are present in an individual only the “dominant” trait will be observed. For a dihybrid cross these statements still hold true but the law of independent assortment can also be observed. This law states that alleles at different loci on a chromosome that encode for different things separate independently of one another. METHOD Before beginning the experiment it was important to determine the sexes of the flies using a dissecting microscope and then to predict which phenotypes would be expressed. To distinguish between the sexes it was helpful to observe size, shape, and color of the flies, and to also check for the existence of sex combs. Only male flies have sex combs. Female flies are usually somewhat larger...
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...Loreen Whitfield 11/6/12 Section 6 Drosophila I. Introduction Over the course of this lab we are to familiarize ourselves with Drosophila, fruit flies, which is an important experimental organism. It is useful for genetic research because of its genome which represents eukaryotic organisms. The life cycle of the fruit fly is short which allows it to be easily observed over its lifetime. Also it can be reproduced and handled in large numbers. From this lab we can expect to learn how to etherize the flies and avoid killing them and to determine the sex of the flies. Finally we will be able to identify the differences between a normal, wild type, and a mutant fly. Determining the sex of the flies can be done because of different characteristics between the sexes. Females tend to be larger than males, an alternating banded posterior, and an oviposterior plate. Males are usually smaller than females and have sex combs located on the forelegs. The normal Drosophila physical characteristics can be grouped into four main features. The body consists of a yellow and gray pigmentation, eyes are brick red, and wings are in an elliptical shape with veins along them. Differentiation from this can result in a mutant fly which are more commonly found in a lab as opposed to nature. Mutant characteristics can appear in one or more different aspects of the Drosophila appearance. The purpose for this lab is to conduct a cross between two different mutations to determine whether they...
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...For several of my college years I worked full time making school very challenging. Over the course of time my grades gradually improved after deciding to quit working. Being in the science field gave me the skills to plan, execute and close any task or project that was presented to me. These are the skills that I feel will make a great and qualified Project Manager. Research Experience My research experience was the highlight of my academic experience throughout college. During my junior year, I worked with cyanobacteria, trying to develop a link between it and mosquitoes. The purpose of my research was to find out how cyanobacteria could be used to kill off mosquitoes. Towards the end of my junior year I worked with fruit flies (Drosophila melanogaster). The purpose of this project was to successfully cross-link (breed) with different types of mutations to...
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...RESEARCH QUESTION: What will be the phenotypic ratio outcome of and F2 generation of red eyes fruit flies crossed with white eyed fruit flies? BACKGROUND INFORMATION: sexually dimorphic . Law of independent assortment Drosophila Melanogaster, the fruit fly completes its life cycle in 10-12 days, makes a large number of offspring, and it has many types of hereditary variations that can be seen with low power microscopes. Drosophila has four pairs of chromosomes, a relatively small number which are easily located in the large salivary glands. Many factors combine to affect the length of the Drosophila life cycle. Temperature affects the life cycle the most. At room temperature the average life cycle of the Drosophila is about 12 days. HYPOTHESIS: That in a sex-lined cross between...
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...pipeline. 2.What is tradeoff and examples of tradeoff. A trade-off (or tradeoff) is a situation that involves losing one quality or aspect of something in return for gaining another quality or aspect. It often implies a decision to be made with full comprehension of both the upside and downside of a particular choice; the term is also used in an evolutionary context, in which case the selection process acts as the "decision-maker". Examples of tradeoff is as follows Trade-off between wage inflation and unemployment. Hint categories include controls for rendering quality and overall time/quality trade-off in the rendering process. Trade-off associated with selection for increased ability to resist parasitoid attack in drosophila melanogaster. Mitigation banking is only suitable for systems which have been shown to be...
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...from the Fruit Fly” I chose this article because the name was very interested to me, and I thought it would be very interesting. I also chose this article because it consisted of theories and experimental conditionings of why we forget thing. This caught my attention because for many, many years I have always wondered why I would forget things. This raised a concern and the urgency to learn this within this lesson because it would occur very frequently to me. As I was growing up, and even throughout my adult hood people close to me also noticed this, and I never know why, until reading more about this issue and how it affect other people as well and why it happens. This article conducted of a conditioning experience that featured a Drosophila melanogaster also known as a fruit flies. Conducting this experience it revealed that the cause underlying forgetting is an active process which is modulate by the learning task and not by internal constraints of memory system. This fly has been the favorite organism for biological research, initially in the field of genetics and now for the fundamental problems in biology freedom the fields of ecology and neurobiology. This was done by taking a group of fruit flies and placing them into a tube for conditioning, of course. This group was exposed to a specific odor and the exposer was paired with an reinforcer of sugar or electrical shock. Then they are removed from the conditioning tube and placed into the second, elongated tube for...
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... BIOL 251 Whittier College Effect of Ebony and Wild Type Phenotypes on the Natural Selection and Fitness of Drosophila November 2015 Effect of Ebony and Wild Type Phenotypes on the Natural Selection and Fitness of Drosophila November 2015 INTRODUCTION: There are many different Drosophila phenotypes. This experiment focuses on the ebony and wild type phenotypes. These phenotypes affect color. The ebony flies more dark and the wild type flies are much lighter. The ebony is recessive and therefore carries two copies of the recessive allele, therefore the Drosophila are homozygotes. But wild type is dominant, meaning that heterozygotes and homozygotes represent the wild type phenotype. A phenotype is a physical characteristic as a result of a genotype affected by its environment (Brooker et al, 2011). A genotype is the set of genes of an individual (Brooker et al, 2011). Drosophila are ideal for this experiment because there is an abundance of them, they reproduce quickly, and they have short life cycle (Jennings, 2011). Natural selection and fitness are related to evolution in a population. Natural selection is when certain traits survive because they are selected for by the environment. These traits enhance or...
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...Eyeless mutation gene located within the second intron of Drosophila melanogaster Justin Lazarus Genetic 300 Abstract The following experiment was conduct over a several week time span to determine and identify the mutation that is causing the eyeless mutation within the Drosophila melanogaster fruit flies. The experiment included genome sequencing and comparison between the Drosophila melanogaster wild type and the Drosophila melanogaster eyeless type. After combining the two different phenotypes. We determined that we were unable to visualize the mutation at a chromosomal level, as both wild-type and eyeless flies looked similar. The experiment involved electrophoresis and Polymerase Chain Reaction (PCR) through which we were able to isolate and amplify the needed DNA eyeless DNA. The difference between the wild-type Drosophila melanogaster and the eyeless Drosophila melanogaster is approximately only 500-nucleotide base pairs. As we see the eyeless phenotype is approximately 3000 base pairs in length while the wild-type phenotype is approximately 2500 nucleotides base pairs in length, a difference of about 500 base pairs. After completing nucleotide sequencing and comparing our data on the blast website, we determined that the eyeless mutation has being interest exons two and three, but more specifically the mutation itself was located within the second intron at base pairs 8264 to 9212. Introduction In the early 20th century scientists had already been acquainted with...
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...The model organism Drosophila Melanogaster has a longstanding history and has contributed historically to Science and society. Model organisms are defined to be a species that have been widely studied because it is easy to maintain and has advantageous breeding abilities in the laboratory. Despite some of its properties that are advantageous in scientific experimentation such as its abundance, affordability, and quick breeding abilities in producing a new generation every 12 days. Historically, the Drosophila Melanogaster was unknown for its characteristics, until the famous biologist Thomas Morgan came to learn about these advantageous abilities. The fruit fly’s life cycle consists of four stages of reproduction, including the egg, larvae,...
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...flies, group lab books, vials, foam plugs, fly-nap, netting, anesthetizing wand, media contain yeast and antifungal agent, plastic cups, paintbrushes, index cards, vial labels, record sheets, and Carolina Drosophila. Then we had to get ready the Drosophila fly vials; to finish these eight actions are essential. Phase one add 1.5 cm of flakes into vial to about 1.5 cm high of the vial. Phase two is to add three to six grain of antifungal agent and yeast into the vial. Phase three is to standard water with one percent propionic acid by showering a little into a Dixie cup then uses a pipette add a few drops of one percent propionic acid to moisturize the flakes. Phase four the flakes should be converted to a blue color all through the vial. Phase five let the vial set for about eight to ten hours, if the vial is dehydrate moisturize again. Phase six flip one net lengthwise and place in the form of a U to offer surface position for the Drosophila to pupate. Phase seven while culturing the drosophila in the vials, keep the vial moisturized. Phase eight labeled the vials....
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...Introduction: The experiments of Beadle and Tatum proposed a hypothesis that stated that certain gene traits are related to particular enzymes that are missing. Investigation #19 allowed students to investigate and identify the chemical differences within species of fruit flies, in order, to understand the actions of their genes. The following materials were used to visually see the chemical differences in Drosophila melanogaster mutants: the eyes from the flies, paper chromatography, a good solvent for the paper chromatography to interact with and a UV light source. The seven species of flies used include: wild type, white, cinnabar, brown, cinnabar brown double mutant, sepia and white apricot. The phenotypes of these species varied from a red pigment, brown pigment and a white pigment. When a red pigment and brown pigment are crossed, the resulting color is brick red....
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...used to understand other complex animals such as humans. “almost 75% of genes responsible for human diseases are observed to have homologs in Drosophila fly” (Pandey, U. B., & Nichols, C. D. ,2011). Moreover, one of the most available and favourable animal model used to study is the fruit Drosophila melanogaster. “Drosophila has been a key experimental subject in genetics since the early 1900s. It was initially chosen to study by T.H. Morgan because it can be raised easily in laboratory, and the life cycle and mating can be arranged inexpensively.” (Scott F., Mike H., & Joan S, 2014). Furthermore, “Drosophila has ~ 68...
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...Linkage Mapping in Drosophila Introduction Common fruit flies, D. melanogaster, have been found as one of the most useful tools in genetic research. The reason behind that it is a popular experimental organism is due to the high likely hood of producing mutant, visible individuals. Geneticist, Thomas Morgan Hunt, was the first to discover the Drosophila as a model organism to study genetic hereditary. His research showed that the species could randomly obtain genetic mutations that could be visible in the parental generation. Since fruit flies have a diploid chromosome number of 8 (haploid 4), chromosomal types are easily identified. Various genetic crosses are able to determine that the x-linked gene is found on chromosome 1, while the autosomal genes are located on the 2-4 chromosomes. Mapping of unknown mutations by reciprocal crosses can identify if the alleles are x-linked or autosomal and if these alleles are dominant or recessive. Once the type of allele is determined, other genetic crosses can determine the location of the chromosome that the mutagen is one. For the x-linked mutations, a three factor test cross can induce map order and distance. The physical distance separating two genes on the chromosome (map distance) is directly related the frequency of recombination between markers during meiosis. The greater the map distance of the genes, the greater the probability that there is crossing over when the chromosomes segregate in meiosis. ...
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...Name: Duc Le Drawer/Group #: 15 PS ID #: 1173948 Three digit mutant code: 200 BIOL 3311 Spring 2015 Lab Section: 14707 Date: 02/06/2015 TA Instructor Name: Tess Doumas Writing Assignment 1: Description of Unknown Mutant Allele Phenotype The unknown mutant gene present in the mutant Drosophila melanogaster causes a change in the wild type phenotypic trait. When we compare the mutant to the wild type, we observe a difference in eye color. We set up multiple comparisons based on sex and maturity. The first setup compares newborns of both wild type and mutant. The wild type displays eyes that are brick red with a faint, black pseudopupil located at the center. The mutant’s eyes also appear red but slightly lighter compared to the wild type. The mutant’s eyes do not have pseudopupils. The second setup compares...
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...Scientific experiments are used to gather new information and knowledge, and the results gained from the experiments are used as tools to study other information about the subject. With this experiment, having Drosophila melanogaster as the subject, the goal is to determine, understand and confirm expected genetic principles of this species such as dominance/recessiveness, autosome/sex linkage, linkage/independent assortment, and genetic map distance if sex linkage does exist. Drosophila melanogaster (D. melanogaster), commonly known as fruit flies, is an excellent organism for genetics studies. Fruit fly is hardy, has a small number of chromosomes (2n=8), completes its life cycle in about 12 days at room temperature, and produces large numbers...
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