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Genetically modified food - Реферат

I. Introduction.

I have chosen this problem because I am extremely interested in biology, ecology and the history of mankind. The problem of genetic modification and cloning is very important at the present time. The theme of genetically modified food is actual as every year it takes the greater place in our diet. Many scientists declare danger of the use of genetically modified food stuffs to health. They warn that consumption of similar products is capable to lead to unpredictable consequences, including mutations. One of big problems of a condition in that area is that genetic engineering is being moved by extreme commercial interests. The biotechnological companies aspire to patent and deduce on the market all new products and new genetically modified organisms (plants and animals), not caring about what collateral consequences genetic changes can have.

To please commercial interests of some huge companies any precaution is rejected: in fact being guided by only scientific approach, it would be necessary to test some generations of plants to be convinced of their safety. It has not been made in a case with modified plants as process of testing can borrow millennia. In my work I will try to describe the positive and negative features of genetic engineering, having resulted possible reasons and examples. In fact now there is a set of disputes and discussions so even the urgency of this theme is proved by a simple example - quantity of existing films and serials about this problem.

Genetically modified products can be toxic and dangerous for people. In 1989 the modification of L-Tryptophan, the food additive, caused death of 37 Americans and made invalids 5000 persons because of causing sufferings and potentially fatal illness of blood. Only after that event the product has been withdrawn from the use. According to special explorations, genetically modified L-Tryptophan was equivalent to previous substances which were made with the help of bacteria of natural type. However it did not correspond to these preparations on parameters of safety. If other tests had been carried out, for example, the test for assimilation by animals and people, the fact that this product was not safe would have become obvious. But such tests had not been carried out.

People have different points of view about whether the genetic modification of food is a good thing – in fact it is quite a controversial topic. Those involved in the biotechnology business insist it is safe and that genetic modification can increase yields, reduce waste and improve the flavour and keeping qualities of products. For example, soft fruits can be made firmer to prevent spoilage during transportation. People in favour of genetic modification also say that better use can be made of agricultural land as crops can potentially be modified to grow in hostile conditions, such as those of a drought; this will help in feeding the world. The later is a vital issue. The same goes for improving the nutritional value of foods. More than 800 million people still go hungry, and 82 countries (half of them in Africa) neither grow enough food, nor can afford to import it. In India alone, 85% of children under five live below the normal, acceptable state of nutrition.

It is well known that the fear of new and unknown things is a peculiar feature of people. People have already forgotten that a few dozens of years ago the world was shocked by the discussion about an opportunity of cloning of human beings. This opportunity appeared after the successful cloning of frogs.

Several years ago the mankind was shocked by reports in mass media about Dolly the Scottish sheep, which was represented as its founders assert, an exact copy of its genetic mother. American bull Jefferson and the bull, deduced by the French biologists appeared later. The prospect of work on cloning of a human being is publicly discussed.

Cloning of bodies and fabrics is the problem number one in the field of transplantology, traumatology and in other areas of medicine and biology. Cloned bodies become a kind of rescue for people who have got in automobile failures or any other accidents or for people who need radical help because of diseases caused by age.

The latest months enabled experts to comprehend soberly the situation, to estimate some methodical and technological difficulties lying in the field of mammal cloning. Cloning of a human being can create unsuccessful copies, ugly creatures, but all humankind will be responsible for his or her ugliness. Opponents of female equality and feminism assure that men will not be necessary if cloning is developed. It is absolutely incorrect from the biological and social points of view. Women were compelled to live without men who had not come back from wars. Hardly it was useful to somebody. And hardly women will be always able to do without man's sexual cells for continuation of future generations.

So first of all we shall try not to fear of new and unknown things. And we shall recollect that cloning constantly occurs in natural conditions when identical twins are born. They are identical in their genetic set. It can be easily proved by an opportunity of changing body parts and fabrics between them. Thus, emotional objections against cloning of people have no rational base.

I would like to be a scientist and carry out the experiments of cloning parts of human body. I am absolutely sure that nobody can clone a person because it is not a biological object, but it is the result of socializing, communication, background mentality, language etc.

II. The Main Body.

Genetically modified food.

What is genetic modification?

Unlike normal methods of reproduction, genetic modification is done in the laboratory by cutting, joining and transferring genes between totally unrelated living things. As a result, combinations of genes which would never occur naturally are produced.

Everyone has heard of Dolly the sheep and experiments in the medial field, but genetic modification is also happening in the food industry. It is possible to isolate and transfer different characteristics between unrelated species or between plants and animals. For example, the introduction of an "anti-freeze" gene from an Arctic fish into tomatoes or strawberries made them resistant to frost.

Around 40% of the world's total crop production is lost to pests and diseases, despite the heavy use of pest-killing chemicals. Cauliflowers are no exception, and suffer damage from aphids and other insects. Scientists have looked to nature to find a solution to this problem and discovered that snowdrops are able to survive attacks from some of the most devastating pests. Snowdrops produce a substance called lectin, which affects insects by interfering with their digestive systems. The task is to transfer the gene for lectin production, and thus the property of insect resistance, into cauliflowers.

It is known that tomatoes, carrots and peppers are rich in carotenoids, which help prevent cancer ant coronary heart disease. To make things easier for us, scientists are working to produce vegetables that are genetically modified to contain increased carotenoid levels. They have already succeeded in creating tomatoes with more than three times the normal "anti-cancer" power.

Animals can also be "engineered". When salmon were modified with the gene for cold resistance from the flounder fish, they grew 10 times as fast as normal salmon because the inserted gene had interfered with their grown harmone gene. A pig was modified with a human gene to make it grow faster and leaner. But these efforts have resulted in numerous problems and serious diseases among the experimental animals. [6]

Genetic modification can save the world.

People have different points of view about whether the genetic modification of food is a good thing – in fact it is quite a controversial topic. Those involved in the biotechnology business insist it is safe and that genetic modification can increase yields, reduce waste and improve the flavour and keeping qualities of products. For example, soft fruits can be made firmer to prevent spoilage during transportation. People in favour of genetic modification also say that better use can be made of agricultural land as crops can potentially be modified to grow in hostile conditions, such as those of a drought; this will help in feeding the world. The later is a vital issue. The same goes for improving the nutritional value of foods. More than 800 million people still go hungry, and 82 countries (half of them in Africa) neither grow enough food, nor can afford to import it. In India alone, 85% of children under five live below the normal, acceptable state of nutrition.

Many, if not all Southern countries, posses the indigenous genetic resources – requiring no further genetic modification – that can guarantee a sustainable food supply. For instance, in a single village of northeast India, 70 varieties of rice are grown... Farmers repeatedly used and enchanted some varieties that were resistant to disease, drought and flood, some that tasted nice, some that were coloured and useful for ritual purposes and some that were highly productive. It seems obvious that there is no need for genetically modified crops. On the contrary, they will undermine food security and biodiversity. The best thing is to sustain existing indigenous agricultural diversity as the basis of a secure and nutritious food base for all. [6]

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