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In recent years a new farming revolution has begun, one that involves the (61) of life at a fundamental level--the gene. The study of genetics has (62) a new industry called biotechnology. As the name suggests, It (63) biology and modern technology through such techniques as genetic engineering. Some of the new biotech companies specialize in agriculture and are working feverishly to (64) seeds that give a high yield, that (65) diseases, drought and frost, and that reduce the need for (66) chemicals. If such goals could be achieved, it would be most (67) . But some have raised concerns about genetically engineered crops. In nature, genetic diversity is created within certain (68) . A rose can be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering, (69) usually involves taking genes from one species and inserting them into another (70) to transfer a desired characteristic. This could mean, for example, selecting a gene which leads to the production of a chemical with anti-freeze (71) from an artic fish, and inserting it into a potato or strawberry to make it frost-resistant. (72) , then, biotechnology allows humans to (73) the genetic wails that separate species. Like the green revolution, (74) some call the gene revolution contributes to the problem of genetic uniformity--some say even more so (75) geneticists can employ techniques such as cloning and (76) culture (培养), processes that produce perfectly (77) copies. Concerns about the erosion of biodiversity, therefore, remain. Genetically altered plants, however, raise new (78) , such as the effects that they may have on us and the environment. "We are flying blindly into a new (79) of agricultural biotechnology with high hopes, few constraints, and little idea of the potential (80) " said science writer Jeremy Rifkin.
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什么是结账？结账的程序包括哪几个步骤？
教师备课需要做好的工作包括：(1)钻研所教学科的（）；(2)熟悉和钻研本门学科的教材；(3)了解学生；(4)准备教法。
为了消除因未达账项而导致的不相符，应根据双方核对后发现的未达账项，编制（），据以调节双方的账面余额。
Passage Two Children live in a world in which science has tremendous importance. During their lifetimes it will affect them more and more. In time, many of them will work at jobs that depend heavily on science--for example, concerning energy sources, pollution control, highway safety, wilderness conservation, and population growth. As taxpayers they will pay for scientific research and exploration. And, as consumers, they will be bombarded (受到轰击) by advertising, much of which is said to be based on science. Therefore, it is important that children, the citizens of the future, become functionally acquainted with science--with the process and spirit of science, as well as with its facts and principles. Fortunately, science has a natural appeal for youngsters. They can relate it to so many things that they encounter--flashlights, tools, echoes, and rainbows. Besides; science is an excellent medium for teaching far more than content. It can help pupils learn to think logically, to organize and analyse ideas. It can provide practice in communication skills and mathematics. In fact, there is no area of the curriculum to which science cannot contribute, whether it is geography, history, language arts, music, or art! Above all, good science teaching leads to what might be called a "scientific attitude". Those who possess it seek answers through observing, experimenting, and reasoning, rather than blindly accepting the pronouncements of others. They weigh evidence carefully and reach conclusions with caution. While respecting the opinions of others, they expect honesty, accuracy, and objectivity and are on guard against hasty judgments and sweeping generalizations. All children should be developing this approach to solving problems, but it cannot be expected to appear automatically with the mere acquisition of information. Continual practice, through guided participation, is needed. People with a scientific attitude ______
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