考研备考的过程漫长而痛苦，在复习中，会遇到很多困难，不少考生付出很多努力却收效甚微，从而产生茫然的失落感；或失去备考的热情与信心。究其原因，无非是考生无法准确找到复习的重点，遇到疑难问题无法得到满意的解答。

　　Is GE food Safe To Eat

　　Traditional plant breeding involves crossing varieties of the same species in ways they could cross naturally. For example, disease－resistant varieties of wheat have been crossed with high－yield wheat to combine these properties. This type of natural gene exchange is safe and fairly predictable.

　　Genetic engineering（GE）involves exchanging genes between unrelated species that cannot naturally exchange genes with each other.GE can involve the exchange of genes between vastly different species, e.g.putting scorpion toxin genes into maize or fish antifreeze genes into tomatoes. It is possible that a scorpion toxin gene, even when it is in maize DNA, will still get the organism to produce scorpion toxin, but what other effects may it have in this alien environment?We are already seeing this problem——adding human growth hormone genes to pigs certainly makes them grow——but it also gives them arthritis and makes them cross－eyed, which was entirely unpredictable.

　　It will be obvious, for example, that the gene for human intelligence will not have the same effect if inserted into cabbage DNA as it had in human DNA——but what side－effect would it have? In other words, is GE food safe to eat? The answer is that nobody knows because long－term tests have not been carried out.

　　Companies wanting a GE product approved in the UK or USA are required to provide regulatory bodies with results of their own safety tests.Monsanto''s soya beans were apparently fed to fish for 10 weeks before being approved. There was no requirement for independent testing, for long－term testing,for testing on humans or testing for specific dangers to children or allergic people.

　　The current position of the UK Government is thatThere is no evidence of long－term dangers from GE foods. In the US, the American Food and Drug Administration is currently being prosecuted for covering up research that suggested possible risks from GE foods.

　　翻译：

转基因食物是否安全

　　传统的植物培育方法，是依照植物自然杂交的方式，进行相同物种的人工杂交。比如，抗病小麦同高产小麦杂交，形成了一种具有双重特性的新的小麦品种。这种自然的基因交换既安全，又具有相当的可预见性。

　　基因工程是在彼此毫无关系的物种之间，相互交换在自然条件下无法交换的基因。它可在有巨大差异的物种之间进行基因交换。比如，将蝎子毒素基因注入玉米，或者将鱼防冻基因注入西红柿。即使在玉米DNA中，蝎子毒素基因依然可能获得有机组织产生蝎子毒素。但是在这种异质的环境中，这种基因产品会有什么其他作用吗？我们实际上已经发现这个问题：将人类生长荷尔蒙基因植入猪的体内，一定会使猪的生长加速，但是同时也使猪患上了关节炎和内斜视，而这一切是完全无法预测的。

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