The term genetically modified organism(GMO)refers to plants, microbes and animals with genes transferred from other species in o

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问题 The term genetically modified organism(GMO)refers to plants, microbes and animals with genes transferred from other species in order to produce certain novel characteristics(for example resistance to pests, or herbicides)and are produced by recombinant DNA technology. Four main sources of hazards of GMO are discussed by scientists worldwide: 1)those due to the new genes, and gene products introduced; 2)unintended effects inherent to the technology; 3)interactions between foreign genes and host genes; and 4)those arising from the spread of the introduced genes by ordinary cross-pollination as well as by horizontal gene transfer.
GM crops contain material, which is not present in them under natural conditions, and they form a part of our daily diet. To understand what effect they can have on us and on our animals, it is very important to study the influence of these GM plants in different organisms for several generations. At present, these studies are lacking from the scientific literature. Also, several detrimental effects of GM crops had been showed on the metabolism of animals. The hazard of GMO was shown for animals and the environment in many investigations. Earlier it was shown that consumption of GM food by animals led to the negative changes in their organisms. Experiments, conducted by A. Pusztai showed that potatoes modified by the insertion of the gene of snowdrop lectin(雪花莲凝集素), stunted the growth of rats, significantly affected some of their vital organs, including the kidneys, thymus(胸腺), gastrocnemius muscles(腓肠肌)and others and damaged their intestines and their immune system.

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答案 转基因生物指的是导人其他物种基因的植物、微生物以及动物,通过运用重组DNA技术,以让这些生物具有某些异常的特征(比如抵抗害虫或除草剂)。科学家们在广泛探讨转基因生物带来的四个主要危害源:1)含有新基因的产物以及引进的基因产品;2)技术本身的非预期效应;3)外源基因和宿主基因之间的相互作用;4)有些基因是通过异花授粉以及水平基因转移产生的,它们的扩散带来的问题。 转基因农作物含有自然条件下它们本身没有的物质,而它们又是我们日常饮食的一部分。为了理解转基因农作物对我们人类以及牲畜的影响,研究属于不同物种的转基因植物连续几代产生的影响是很有必要的。目前,这些研究缺乏来自科学文献的支持。并且转基因作物也有一些有害的影响已经波及动物的新陈代谢。在许多研究中,转基因生物的危害都已经在动物以及环境中显现出来。早在初期,动物吃了转基因食物后,出现了一些负面的变化。A.普兹泰做的实验显示,插入雪花莲凝集素基因的土豆使老鼠发育不良,极大地影响到了老鼠的一些重要器官包括肾脏、胸腺、腓肠肌以及其他器官,损害了他们的肠道以及免疫系统。

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