Реферат

Реферат на тему Genetic Food Essay Research Paper Introduction The

Работа добавлена на сайт bukvasha.net: 2015-06-01

Поможем написать учебную работу

Если у вас возникли сложности с курсовой, контрольной, дипломной, рефератом, отчетом по практике, научно-исследовательской и любой другой работой - мы готовы помочь.

Предоплата всего

от 25%

Подписываем

договор

Выберите тип работы:

Скидка 25% при заказе до 26.12.2024


Genetic Food Essay, Research Paper

Introduction The use of genetically engineering in agriculture and food production has an impact, not only on the environment and biodiversity, but also on human health. Therefore, thorough biosafety assessment requires, not only an evaluation of environmental impacts of genetically engineered organisms, but also an assessment of the risks that genetically engineered food pose for the health of consumers. Let us take deeper look at some of the aspects related to genetically engineered foods. What is Genetic Engineering? Genetic engineering is a laboratory technique used by scientists to change the DNA of living organisms. DNA is the blueprint for the individuality of an organism. The organism relies upon the information stored in tits DNA for the management of every biochemical process. The life, growth and unique features of the organism depend on its DNA. The segments of DNA, which have been associated with specific features or functions of an organism, are called genes. Molecular biologists have discovered many enzymes, which change the structure of DNA in living organisms. Some of these enzymes can cut and join strands of DNA. Using such enzymes, scientists learned to cut specific genes from DNA and to build customized DNA using these genes. They also learned about vectors, strands of DNA like viruses, which can infect a cell and insert themselves into its DNA. Scientists started to build vectors, which incorporated genes of their choosing and used vectors to insert these genes into the DNA of living organisms. Genetic engineers believe that they can improve the foods we eat by doing this. At first glance, this might look exciting to some people. Deeper consideration reveals some advantages and serious dangers. What are the advantages of Genetically Engineered Food? Genetic engineering gives today s researchers considerable advantages in plant breeding programs. + Predictability Scientist can identify the specific gene for a given trait, make a copy of that gene for insertion into a plant, and be certain that only the new gene is added to the plant. This eliminates the backcrossing , traditional plant breeders must do to eliminate extraneous undesired genes that are frequently introduced when using cross-hybridization. + Significant acceleration of the development timetable. New technique takes about 5 years to remove the undesirable traits compared to 12 years of process with the traditional techniques. Plant breeders do not use recombinant DNA techniques exclusively. Instead they use a combination of new and traditional methods to provide a plant with quality, yield, weather and pest resistance and other desirable traits. + Improved quality with more choices for the customers. Genetically engineered food especially fruits and vegetables allow to have plenty of time for shipping and sale and it helps to keep the them stay ripe without getting rotten. Some of the fruits and vegetables need warm climates to grow, so most off-season store them must travel a long way after they are picked. One example is the Flavr Savr tomatoes. To survive their journey intact, tomatoes are picked while they are green, which is a food which is a good way to avoid bruising, but which results in a tomato that is often described as having the consistency and mouth-feel of a tennis ball. In the case of Flavr Savr tomatoes, the company solved the rotting problem by inserting a reversed copy- an antisense gene of the gene that encodes the enzyme that results in tomato spoilage. This suppresses the enzyme that results in rotting, allowing the tomato to stay ripe, but not rot, up to 10 days plenty of time for shipping and sale. Refrigeration is not necessary. What are the dangers of Genetically Engineered Food? + Is it safe to eat? There has been no adequate testing to ensure that extracting genes that perform an apparently useful function as part of that plant or animal is going to have the same effects if inserted into a totally unrelated species. To consumers, most genetically engineered foods are essentially foods with added substances, usually proteins. This is because genes are translated into proteins by cells. Therefore, when a genetic engineer adds, say, a bacterial gene to a tomato, he or she is essentially adding a bacterial protein to that tomato. In most cases these added proteins would likely prove safe for human consumption. Nevertheless, just as with conventional food additives, substances added to foods via genetic engineering may in some instances prove hazardous. Unfortunately, food allergies are poorly understood, and in many cases scientists will not be able to test potential allergenicity of genetically engineered foods. Even if there was some testing, the long term affects to humans, animals, and the environment from these modified genes escaping and mixing with unmodified ones are unknown. + Health Hazards There are several differences between the normal breeding process and the artificial genetic manipulation process. One key difference is the use of highly infectious viruses for artificial genetic manipulation as a promoter to witch on the introduced gene. Some of the viruses used are highly infectious. Genetic manipulation can increase the risk that the plant will develop toxic or allergy-causing compounds. Another possibility is that regulate exposure to foreign DNA and RNA material inserted into these artificial foods could cause allergic reactions or autoimmune disease. Allergens A number of molecular mechanisms have also been identified through which the genetic manipulation of food producing organisms could generate new allergens or increase the allergenicity of proteins normally present in food producing organisms. Because allergen-carrying transgenic foods will in most cases maintain the appearance of their natural, non-allergenic counterparts, they pose a serious hazard to the consumer. Consumer will not be able to avoid these allergenic foods, because they will not be able to distinguish them from the corresponding natural foods. The labeling of all genetically engineered foods would, of course, solve this problem and would also make it possible for health authorities to trace allergen problem that arise. Toxins & Poisons In addition to allergenicity, recombinant proteins could manifest a variety of other biological activities, and in the case of recombinant enzymes, could catalyze the production of other compounds with biologic activities not normally present in a particular food. For instance such substances could act as toxins or irritants and could act at the biochemical, cellular, tissue or organ levels to disrupt a range of physiological functions. An example of a class of genetically engineered foods that are of particular concern are those that have been modified to produce biological control agents such as the family of insecticidal Bt enterotoxins. The Bt toxin, which has been used topically in organic farming, has powerful biological activity. If consumed in larger amounts it can become a toxin. Plants genetically-manipulated to produce Bt toxin produce at least 1000 times more Bt toxin per acre than does a heavy application of Bt directly on plants. There was another case where one company genetically engineered a microorganism to produce L-tryptophan at high levels killed almost 37 people and made 1500 permanently disabled by using that product. This was due to the presence of traces of a toxic contaminant. This contaminant was extremely powerful. Damage to Nutrition quality A 1999 study by Dr. Marc Lappe published in the Journal of Medicinal Food found that concentrations of beneficial phytoestrogen compounds thought to protect against heart disease and cancer were lower in genetically modified soybeans than in traditional strains. These and other studies, including Dr. Pusztai s, indicate that genetically engineered food will likely result in foods lower in quality and nutrition. For example the milk from cows injected with rBGH contains higher levels of pus, bacteria, and fat. Sources of risk Unmodified Organism (UMO) The genetic engineering of foods involves the introduction of new genetic information into a food-producing organism. Some of the health risks associated with genetically engineered foods can be anticipated on the basis of what we already know about the characteristics of the organism in its unmodified state (called the unmodified organism UMO) from which the genetically engineered organism is to be generated. Gene Source (GS) Other aspects of the risk associated with genetically engineered foods can be deduced from the characteristic of the organism that is the source of the genetic information introduced into the food producing organism (called the gene source or GS). For instance, if a gene derived from peanuts is introduced into a tomato, food produced from the resulting genetically engineered tomato might cause allergic reactions in people that are allergic to tomatoes (the unmodified organism) or to peanuts (the gene source). Procedure of Genetic Engineering In addition to UMO and GS, there is another source of potential risks, which is the procedure of genetic engineering itself. Current recombinant DNA methods and those likely to be developed in the future are all capable of accidentally introducing unintended changes in the function and structure of the food-producing organism. As a result, the genetically engineered food may have characteristics that were not intended by the genetic engineer, and that cannot be foreseen on the basis of the known characteristics of the unmodified organism or gene source. Labeling Issues FDA requires labeling of genetically engineered foods under certain exceptional circumstances. Since most genetically engineered foods will be indistinguishable in appearance from non-engineered foods, consumers will generally not know what they are buying. FDA ignores consumers right to know by ignoring longstanding regulations that require in most circumstances that manufactures label foods to disclose their ingredients. For example, researchers have genetically engineered vegetables to produce a new protein sweetener. Existing FDA regulations mandate that companies disclose sweeteners added to canned vegetables via conventional means. Yet, FDA will not require that proteins sweeteners added to vegetables via genetic engineering be labeled as ingredients. Labeling is vital to food allergic individuals, who need to know when their purchases are potentially allergenic. FDA will require labeling of foods genetically engineered to contain potential allergens from only the most commonly allergenic foods a requirement that threatens individuals with less common food allergies. FDA also will require labeling if a company uses genetic engineering techniques to change a food s composition significantly. For example, when one manufacturer modified canola to produce increased levels of lauric and myristic acids in the seed oil, FDA agreed that the common or usual name for this oil would be laurate canola oil in order to distinguish it from traditional canola oil. Some vegetarians and individuals who follow religious dietary laws have told FDA that they want to know when animal genes are added to plants used as foods. FDA has taken no steps to accommodate their dietary beliefs and restrictions. What can you do as a consumer ? Look for soy products and ingredients like tofu, tempeh, miso, soy sauce, soymilk that are organic. All other soy ingredients are almost genetically manipulated and herbicide- treated. The same is true for canola, corn, dairy products and potatoes. Look for organic corn, potato and dairy ingredients when you shop. It may be best to avoid canola altogether because it is rarely organic and is usually chemically treated. A recent experiment conducted by independent expert DR. Alpad Puszatai in the United Kingdom has shown that genetically manipulated foods can, when fed to animals in reasonable amounts, cause very gradual organ damage and immune system damage. Conclusion Reading the label is an important part of shopping for a consumer. If consumers do not want to consume genetically manipulated foods, they can always contact the store managers and ask them to carry more organic foods in the store. Most of the time the food product manufacturers also pay attention to consumers feed back. Further, if one has questions or concerns about such issues, one can always contact a nutritionist who is aware and well informed of the pros and cons of Genetically Engineered Foods.


1. Сочинение на тему Гимн жизни О стихотворении Пушкина Вновь я посетил
2. Реферат С-r правой почки T1N0N0. Хронический пиелонефрит
3. Курсовая на тему Основной капитал предприятия Анализ использования основного капита
4. Реферат Технология разрешения конфликтов 2
5. Реферат на тему Hiroshima Essay Research Paper John Hersey
6. Реферат на тему Conflict In Kosovo Essay Research Paper For
7. Сочинение на тему Достоевский ф. м. - Раскольников лужин свидригайлов три ипостаси зла
8. Реферат на тему Richard W Sears And Sears Roebuck
9. Курсовая на тему Олигополия 2
10. Сочинение на тему Однозначные и многозначные слова Прямое и переносное значения слова