Drosophila and the cinnabar Gene
Drosophila melanogaster, commonly known as fruit fly, is mainly used as a human disease model organism for genetic analysis. It was during the 20th century that D. melanogaster was considered as the most significant model organism. D. melanogaster is small in size, and it has a short life span with a good reproduction rate, perfect for raising in large number and generation counts for genetics experiments. Additionally, it has a small genome which makes it easier for geneticists to keep track of changes in molecular level. Geneticists were able to uncover many human genetic diseases through the homologous genome of human and fruit flies. It started out with a small group of people led by Thomas Hunt Morgan at Columbia University. Many principles and rules of transmission genetics that are still being used in the generation of today were established in the laboratory of Dr. Morgan. Many animal models were being used before fruit flies. Using the whole-animal as a model set limitations to the types and amounts of experiments can be conducted. The use of Drosophila was able to led geneticists to overcome these limitations with tremendous promises in finding greater quality results. It was Frank Lutz, who wrote many papers on Drosophila, which introduced Drosophila to Dr. Morgan. Many experimental works on plants and animals were carried out on Drosophila instead. Through Drosophila, the discovery of mutation, recombination, relocation of chromosome, and many others were made possible. The cinnabar, cn, gene encodes an enzyme essential in the eye color formation of drosophila. It codes for the enzyme, kynurenine-3-monooxygenase, that is essential in the biological pathway of ommochrome for the brown pi...
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...ine, the mutation of cn1 or cn35k occurred. When the mutations of cinnabar happened, the biological pathway of ommochrome will be halted, and the brown pigment, xanthommatin, production gets inhibited, resulting in Drosophila to have bright red eyes.
The phenotypic characteristic mutations of Drosophila are an essential aspect matter in studying and understanding newly found human genetic diseases. The mechanism of enzymes metabolize tryptophan, and the intermediates of the biological pathway of ommochrome, oxidation of kynuenine to 3-hydroxykynuenine, of the cinnabar gene allowed geneticists to study the possibilities of neurotransmission factors in many brain disease such as Alzheimer’s and Parkinson’s disease. The biological pathway of cinnabar mutations mimics a molecular evaluation of an approach that linking to the human biological processes brain system.
The white (w) eye color gene is located on the X chromosome at 1.5 genetic map units (1). The mutation is also recessive, meaning that each fly has different copies of the gene if they are either male or female (2). In wild-type Drosophila, the brick red color is visible due to the combination of two pigments, brown and scarlet. The synthesis of drosopterin for bright red pigments is controlled by the (bw+) gene and the synthesis of ommochromes for brown pigments is controlled by the (st+) gene (7). Therefore, there are two pigment synthesis pathways that must be working in order for the flies to express the brick red eye color. In addition, transport proteins are responsible for transporting both pigments into the eye in order to express the color (8). Thus, both the pathways responsible for the synthesis of brown and red pigments must work properly as well as the genes that encode for transport proteins. Despite having white eyes, Drosophila flies with this mutation still experience normal eyesight
Conclusion for class di-hybrid cross: The p value 0.779 is in the non-significant range in the chi square table. The null hypothesis is therefore correct. Sepia eyes and vestigial wings in the flies is a mutation in the genes that is not linked meaning it is a product of independent assortment.
In this experiment, Mendelain Models are observed. The purpose of the experiment is to understand how traits are passed from one generation to the other as well as understanding the difference between sex linked and autosomal genes. One particular trait that is observed in this experiment is when a fly is lacking wings, also known as an apterous mutation. In this experiment, we will determine whether this mutation is carried on an autosomal chromosome or on a sex chromosome. The data for this experiment will be determined statistically with the aid of a chi-square. If the trait is autosomal, then it will be able to be passed to the next generation on an autosomal chromosome, meaning that there should be an equal amount of male and
Examining the Crosses Between Drosophila Fruit Flies Introduction The major topic of this experiment was to examine two different crosses between Drosophila fruit flies and to determine how many flies of each phenotype were produced. Phenotype refers to an individual’s appearance, where as genotype refers to an individual’s genes. The basic law of genetics that was examined in this lab was formulated by a man often times called the “father of genetics,” Gregor Mendel. He determined that individuals have two alternate forms of a gene, referred to as two alleles.
Importance of Leadership Leadership is something that stands out in people. In a group, people tend to look for the strongest person to follow. However, the strongest person may not be the best choice to follow. In Lord of the Flies by William Golding, Ralph and Jack each have leadership qualities. Jack is probably the stronger of the two; however, Ralph is a better leader.
Similar to how we used water on both sides as a control in the baseline experiments, our first test was with dim light on both sides. To set up the chamber, we put 52 fruit flies in the double-sided chamber and sealed it tightly. Make certain to get at least 20 flies in the experiment for a larger set of data. That is why we put 52 flies in the choice chamber- to get substantial data. In order to count the number of flies on each side, draw a line going down the middle of the choice chamber to divide it into two halves. Side A is one half, and Side B is the other half. In this lab, we used red, blue, black, green, and 2 white light bulbs throughout the experiment. Additionally, to measure the intensity of the light hitting the choice chamber,
Though Huntington’s is caused by a mutation, research is still being focused on its pathogenesis to gain a better understanding of the disease. Research done by Wider and Luthi-Carter (2006) shows that the main pathological causes of Huntington’s are atrophy and gliosis of the caudate nucleus and the putamen, which become noticeable and statistically significant around ten years prior to disease onset. The research completed by Wider and Luthi-Carter (2006), also shows a significant loss of GA...
The Catechol-O-methyltransferase (COMT) gene is a specialised type of enzyme, which is involved in the degradative processes of catecholamines. This process is a necessity in the human body, as prolonged exposure to catecholamines is detrime...
Lord of the Flies: Final Essay Exam. Are the defects of society traced back to the defects of human nature? The defects of society, and how it relates to the defects of human nature, can be explained with the savagery that drives the defects of society and the same savagery that drives the defects of human nature. In this story, Lord of the Flies, Golding shows the id, ego, and superego within the characters in the book. Golding represents the id with Jack, whereas the id says “I want, and I want it now,” and Jack constantly wants and needs power, and wants his way in every situation.
The path physiology of Parkinson’s disease is the pathogenesis if Parkinson disease is unknown. Epidemiologic data suggest genetic, viral, and environmental toxins as possible causes. Nigral and basal loss of neurons with depletion of dopamine, an inhibitory neurotransmitter, is the principal biochemical alteration in Parkinson disease. Symptoms in basal ganglia disorders result from an imbalance of dopaminergic (inhibitory) and cholinergic (excitatory) activity in the caudate and putamen of the basal ganglia.
Almost all biology students learn the fundamentals of gene expression, DNA contains information which is transcribed into RNA to create protein. Students however, are not taught of RNA Interference, the biological process where RNA molecules inhibit a gene’s expression, RNAi for short. While RNAi is a fairly new discovery, its use in modern biological research is groundbreaking. RNA Interference works by binding Double-stranded RNA molecules (siRNA) to a complementary messenger RNA. The enzymes Dicer and Slicer then cleave the chemical bonds which hold the messeger RNA in place and prevent it from delivering protein silencing instructions thus, the term, Gene Silencing. This phenomenon was first discovered by Richard Jorgensen in 1990 when he was trying to produce deeper purple colored petunias by introducing more purple pigment genes to the flower. To his surprise, the purple petunia turned completely white and got the opposite of his predicted result. At the time Jorgensen coined this effect, “Cosuppression”. It was not until 1998 that Andrew Fire and Craig, C Mello explained the process of RNAi and discovered its use in Caenorhabditis elegans (C. Elegans). In 2006 Fire and Mello won the Nobel Prize in Physiology or Medicine “for their discover of RNA Interference – gene silencing by double stranded RNA”. They utilized the nematode, C. Elegans due to its whole genome being sequenced. This unique characteristic allows for every gene to be tested
The novel; “Lord of the Flies” is a highly renowned novel written by William Golding and published in 1954. The novel embodies many themes and events that are mysterious and unanticipated for the reader. During the course of the essay I will explain how the conch shell that is found at the foundation of the first chapter plays a significant role throughout the novel and how diverse themes are brought on from this influential shell. This essay will express an opinion on the conch shell, in the end has more power and order than the actual ‘beast’ that is signified on the island. I will also explore the social leadership of the conch throughout the novel which will also touch on a few themes that the conch shell plays a role in. The conch shell is one of the first real theme/symbol that readers are introduced too and stands its power for most of the novel which is why it should be explored in further detail in this essay.
If you had a choice between a burger and a bowl of crickets, I think I would know which you choose to eat. As disturbing as this sounds, in the near future we may not have that choice. With our annual protein consumption rising, and Europe’s protein sources decreasing, coupled with a growing population, we may have only one alternative… Insects.
Lord of the Flies, written by William Golding is an allegory in novel format about a group of young boys stranded on an island without adults. The story is a microcosm in which Golding reveals his opinions about humanity and the society that has been created. Golding, using an abundance of symbols and themes to show his beliefs on politics, religion and society as a whole. Throughout the story Golding shows that people look at the outer appearance of situations instead of really looking into what is happening. This leads them to making poor decision for society, especially when it comes to leadership. The leaders that are chosen can have a truly damaging effect on the mortality of people and they can even be followed religiously. This is detrimental
Specifically, his work with eye color genes, in Drosophila, led to these discoveries which form the basis of the modern science of genetics. As a result of his work, Drosophila became a major model organism in contemporary