题干

作为一种常用的现代生物技术,转基因技术已被广泛应用于生产当中。你的生活中有转基因产品吗?你了解转基因产品的生产原理吗?你对转基因产品持什么态度?请阅读下面的资料并回答问题。

资料1:苏云金芽孢杆菌是一种细菌,体内有“杀虫蛋白”基因(简称BT基因)。将该基因转入水稻中,可以生产出含有BT蛋白的大米,名为BT大米。BT蛋白能使食用它的昆虫幼虫死亡,但目前尚未发现BT蛋白对哺乳动物有明显的毒害作用。

资料2:—般来说,DNA和蛋白质彻底分解成小分子物质后才能被吸收,即使食用了BT 大米,人体内也不会有BT基因和蛋白。然而,近年来科学家发现,存在未经消化的蛋白质被吸收进入人体的现象。

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      You either have it, or you don’t-a sense of direction. But why is it that some people could find their way across the Sahara without a map while others can lose themselves in the next street?
     Scientists say we’re all born with a sense of direction, but it is not properly understood how it works. One theory is that people with a good sense of direction have simply worked harder at developing it. Research being carried out at Liverpool University supports this idea and suggests that if we don’t use it, we lose it.
   “Children as young as seven have the ability to find their way around,” says Jim Martland, research director of the project. “However, if they are not allowed out alone or are taken everywhere by car, they never develop the skills.”
Jim Martland also emphasizes that young people should be taught certain skills to improve their sense of direction. He makes the following suggestions:
    If you are using a map, turn it so that it relates to(与……有联系) the way you are facing.
   If you leave your bike in a strange place, put it near something like a big stone or a tree-something easy to recognize. Note landmarks on the route as you go away from your bike. When you return, go back along the same route.
   Simplify(简化) the way for finding your direction by using lines such as streets in a town, streams, or wells in the countryside to guide you. Count your steps so that you know how far you have gone and note any landmarks such as towerblocks or hills which can help to find out where you are.
   Now you will never get lost again!