[外语类试卷]考博英语(阅读理解)练习试卷10及答案与解析.doc
《[外语类试卷]考博英语(阅读理解)练习试卷10及答案与解析.doc》由会员分享,可在线阅读,更多相关《[外语类试卷]考博英语(阅读理解)练习试卷10及答案与解析.doc(10页珍藏版)》请在麦多课文档分享上搜索。
1、考博英语(阅读理解)练习试卷 10及答案与解析 一、 Reading Comprehension 0 The discovery of the obesity gene in humans half a decade ago offered evidence that chronic weight gain is the consequence of a mismatch between nature and nurture. Simplistic explanations, such as blaming obesity on a drop in fat consumption, ignor
2、e scientific reality. One well-known reason for this is that dietary fat converts to body fat more efficiently than does protein or carbohydrate, but recently scientists have uncovered what appears to be an equally important factor. Some researchers in universities are investigating the possibility
3、that high levels of fat and fructose(果糖 )are mucking up our brain chemistry, and thereby muting the signals that would normally tell us to put down the fork. These signals are produced by peptides(缩氨酸 ),which are regulated by a number of hormones. Under normal conditions these hormones help maintain
4、 a stable body weight by adjusting levels of the peptides that control eating. But a diet loaded with fat and fructose hampers the regulation of these hormones. Complicating matters still further is that the brain loses its ability to respond to these hormones as body fat increases so the obese are
5、doubly penalized. Other researchers are finding evidence that constant exposure to fat and sugar can cause some humans to crave them as they do an addictive drug. A Princeton University psychologist recently showed that rats fed a high sugar diet were, when the sugar was removed, thrown into a state
6、 of anxiety similar to that seen in withdrawal from morphine or nicotine. Sarah Leibowitz, a neurobiologist, believes that frequent exposure to fatty foods may configure the brain to crave still more fat. She has shown in animal studies that galanin, a brain peptide that simulates eating behavior an
7、d decreases energy expenditure, increases when the animal eats a high-fat diet. There are many factors contributing to the explosion of obesity in the United States, and the world, but the radical changes in the composition of our diet are first among them. While scientific work in this arena is in
8、its infancy, its already clear that varying the amount of fat and other nutrients in the diet affects brain chemistry by activating certain genes, and this in turn directs our dietary preferences. (365 words) 1 What is the main idea of this passage? ( A) Dropping in fat consumption attributes to obe
9、sity. ( B) A new theory of obesity a diet affecting brain chemistry. ( C) The obesity gene in humans was found half a decade ago. ( D) Explosion of obesity can be controlled. 2 Which is NOT the newest discovery? ( A) Dietary fat turns to body fat more efficiently than does protein or carbohydrate. (
10、 B) Disordered brain chemistry due to high levels of fat can not prevent us from eating. ( C) Diet rich in fat and fructose hampers the regulation of the hormones concerned. ( D) Fat and sugar are addictive like drugs. 3 Which is the main cause of obesity according to the passage? ( A) Less physical
11、 exercises. ( B) Oversleeping. ( C) Irrational composition of our diet. ( D) Ageing. 4 “In its infancy“ (Line 3, Para. 4) means_. ( A) in the prime of life ( B) at its best ( C) in poverty ( D) at its primitive stage 5 What can NOT be inferred from the whole passage? ( A) The obesity gene in humans
12、was discovered five years ago. ( B) Unbalance between nature and nurture is one of the causes of obesity. ( C) Fat can directs our dietary preferences. ( D) We shouldnt eat any sugar and fat any more in the future. 5 Coincident with concerns about the accelerating loss of species and habitats there
13、has been a growing appreciation of the importance of biological diversity from the number of species in a particular ecosystem to the health of the Earth and human being. Much has been written about the diversity of terrestrial organisms, particularly the exceptionally rich life associated with trop
14、ical rain-forest habitats. Relatively little has been said, however, about diversity of life in the sea even though coral reef systems are comparable to rain forests in terms of richness of life. An alien exploring Earth would probably give priority to the planets dominant, most distinctive feature
15、the ocean. Humans have a bias toward land that sometimes gets in the way of truly examining global issues. Seen from far away, it is easy to realize that landmasses occupy one-third of the Earths surface. Given that two-thirds of the Earths surface is water and that marine life lives at all levels o
16、f the ocean, the total three-dimensional living space of the ocean is perhaps 100 times greater than that of land and contains more than 90 percent of all life on Earth even though the ocean has fewer distinct species. The fact that hall of the known species are thought to inhabit the worlds rain fo
17、rests does not seem surprising, considering the huge numbers of insects that comprise the bulk of the species. One scientist found many different species of ants in just one tree from a rain forest. While every species is different from every other species, their genetic makeup constrains them to be
18、 insects and to share similar characteristics with 750 000 species of insects. If basic, broad categories such as phyla and classes are given more emphasis than differentiating between species, then the greatest diversity of life is unquestionably the sea. Nearly every major type of plant and animal
19、 has some representation there. To appreciate fully the diversity and abundance of life in the sea, it helps to think small. Every spoonful of ocean water contains life on the order of 100 to 100 000 bacterial cells plus assorted microscopic plants and animals, including larvas of organisms ranging
- 1.请仔细阅读文档,确保文档完整性,对于不预览、不比对内容而直接下载带来的问题本站不予受理。
- 2.下载的文档,不会出现我们的网址水印。
- 3、该文档所得收入(下载+内容+预览)归上传者、原创作者;如果您是本文档原作者,请点此认领!既往收益都归您。
下载文档到电脑,查找使用更方便
2000 积分 0人已下载
下载 | 加入VIP,交流精品资源 |
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 外语类 试卷 英语 阅读 理解 练习 10 答案 解析 DOC
