Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.The first two decades of this century were dominated by the microbe hunters. These hunters had tracked down one after another of the microbes responsible for the most dreaded scourges of many centuries: tuberculosis, cholera, diphtheria. But there remained some terrible diseases for which no microbe could be incriminated: scurvy, pellagra, rickets, beriberi. Then it was discovered that these diseases were caused by the lack of vitamins, a trace substance in the diet. The diseases could be prevented or cured by consuming foods that contained the vitamins. And so in the decades of the 1920's and 1930's, nutrition became a science and the vitamin hunters replaced the microbe hunters.In the 1940's and 1950's, biochemists strived to learn why each of the vitamins was essential for health. They discovered that key enzymes in metabolism depend on one or another of the vitamins as coenzymes to perform the chemistry that provides cells with energy for growth and function. Now, these enzyme hunters occupied center stage.You are aware that the enzyme hunters have been replaced by a new breed of hunters who are tracking genes - the blueprints for each of the enzymes - and are discovering the defective genes that cause inherited diseases - diabetes, cystic fibrosis. These gene hunters, or genetic engineers, use recombinant DNA technology to identify and clone genes and introduce them into bacterial cells and plants to create factories for the massive production of hormones and vaccines for medicine and for better crops for agriculture. Biotechnology has become a multibilliondollar industry.In view of the inexorable progress in science, we can expect that the gene hunters will be replaced in the spotlight. When and by whom? Which kind of hunter will dominate the scene in the last decade of our waning century and in the early decades of the next? I wonder whether the hunters who will occupy the spotlight will be neurobiologists who apply the techniques of the enzyme and gene hunters to the funtions of the brain. What to call them? The head hunters. I will return to them later.Which of the following can be cured by a change in diet?A.Tuberculosis B.Cholera C.Cystique fibrosesD.Pell Agra
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.On April 3, 1972, a man came out of the Hilton hotel in Manhattan and started walking down the street. He stopped, (26)______ his hand with a strange object in it, put it to his ear and started to talk into it. This was the beginning of mobile phone (27)_______, more than 30 years ago. That man was Motorola's project manager, Martin Cooper, who was (28)______ his 34th birthday that day. The strange object was the first mobile phone, which was nicknamed "the shoe" because of its unusual (29)_______. Mr. Cooper had gone to New York to introduce the new phone. The first call he made was to his rival, Joe Engel at AT&T's research centre. Engel was responsible for the development of the radiophones for cars. "I called him and said that I was talking on a real mobile phone (30)_____ I was holding in my hand," said Cooper. "I don't remember what he said in reply, but I'm sure he wasn't happy." The quality of the call was very good, because although New York had only one base station at that time, it was being used by only one user - Martin Cooper.(30)_____A.that B.when C.as D.how
_______(6)A.expandingB.turingC.breakingD.damaging
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 42.Life in the UniverseExobiology is the study of life that originates from outside of Earth. As yet, of course, no such life forms have been found. Exobiologists, however, have done important work in the theoretical study of where life is most likely to evolve, and what those extrateưestrial life forms might be like.What sorts of planets are most likely to develop life? Most scientists agree that a habitable planet must be terrestrial, or rock-based, with liquid surface water and biogeochemical cycles that somewhat resemble Earth’s. Water is an important solvent involved in many biological processes. Biogeochemical cycles are the continuous movement and transformation of materials in the environment. These cycles include the circulation of elements and nutrients upon which life and the Earth’s climate depend. Since (as far as we know) all life is carbon-based, a stable carbon cycle is especially important.The habitable zone is the region around a star in which planets can develop life. Assuming the need for liquid surface water, it follows that most stars around the size of our sun will be able to sustain habitable zones for billions of years. Stars that are larger than the sun are much hotter and bum out more quickly; life there may not have enough time to evolve. Stars that are smaller than the sun have different problem. First of all, planets in their habitable zones will be so close to the star that they will be “tidally locked” – that is one side of the planet will always face the star in perpetual daylight with the other side in the perpetual night. Another possible obstacle to life on smaller stars is that they tend to vary in their luminosity, or brightness, due to flares and “star spots”. The variation can be large enough to have harmful effects on the ecosystem.Of course, not all stars of the right size will give rise to life; they also must have terrestrial planets with the right kind of orbits. Most solar systems have more than one planet, which influence each other’s orbits with their own gravity. Therefore, in order to have a stable system with no planets flying out into space, the orbits must be a good distance from one another. Interestingly, the amount of space needed is roughly the width of a star’s habitable zone. This means that for life to evolve, the largest possible number of life-supporting planets in any star’s habitable zone is two.Finally, not all planets meeting the above conditions will necessarily develop life. One major threat is large, frequent asteroid and comet impacts, which will wipe out life each time it tries to evolve. The case of Earth teaches that having large gas giants, such as Saturn and Jupiter,.in the outer part of the solar system can help keep a planet safe for life. Due to their strong gravitation, they tend to catch or deflect large objects before they can reach Earth.It can be inferred from paragraph 3 that A.the Earth is in the sun’s habitable zoneB.the Earth is tidally locked to the sunC.the sun varies in its luminosity D.variations in luminosity help life to develop
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.“Shall I help you do the dishes, Carlo?” said Robert.A.Robert suggested helping Carlo with the dishes.B.Robert suggested to help Carlo do the dishes.C.Robert offered Carlo to help do the dishes.D.Robert offered to help Carlo do the dishes.
Read the following passage and write the letter A, B, C or D on the top of the first page to indicate the correct answer to each of the questions. In 1972. a century after the first national park in the United States was established at Yellowstone, legislation was passed to create the National Marine Sanctuaries Program. The intent of this legislation was to provide protection to selected coastal habitats similar to that existing for land areas designated as national parks. The designation of an areas a marine sanctuary indicates that it is a protected area, just as a national park is. People are permitted to visit and observe there, but living organisms and their environments may not be harmed or removed.The National Marine Sanctuaries Program is administered by the National Oceanic and Atmospheric Administration, a branch of the United States Department of Commerce. Initially, 70 sites were proposed as candidates for sanctuary status. Two and a half decades later, only fifteen sanctuaries had been designated, with half of these established after 1978. They range in size from the very small (less than 1 square kilometer) Fagatele Bay National Marine Sanctuary in American Samoa to the Monterey Bay National Marine Sanctuary in California, extending over 15,744 square kilometers.The National Marine Sanctuaries Program is a crucial part of new management practices in which whole communities of species, and not just individual species, are offered some degree of protection from habitat degradation and overexploitation. Only in this way can a reasonable degree of marine species diversity be maintained in a setting that also maintains the natural interrelationships that exist among these species.Several other types of marine protected areas exist in the United States and other countries. The National Estuarine Research Reserve System managed by the United States government, includes 23 designated and protected estuaries. Outside the United States, marine protected-area programs exist as marine parks, reserves and preserves.Over 100 designated areas exist around the periphery of the Caribbean Sea. Others range from the well-known Australian Great Barrer Reef Marine Park to lesser-known parks in countries such as Thailand and Indonesia, where tourism is placing growing pressures on fragile coral reef systems. As state, national, and international agencies come to recognize the importance of conserving marine biodiversity, marine projected areas whether as sanctuaries,parks, or estuarine reserves, will play an increasingly important role in preserving that diversity.The passage mentions which of the following as a threat to marine areas outside the United States? A.Limitations in financial support B.The use of marine species as food C.Variability of the climate D. Increases in tourism
The main idea of the passage is that ..............A.there are life-supporting characteristics on EarthB.Earth is predominantly waterC.Earth has no common charateristics with other planetsD.Earth is the only planet with a moon
The word "fuel" in line 2 means.....................A.foodB.mealC.nutritionD.energy
The author implies that there is cause for concern if consumers with limited incomes buy organic foods instead of conventionally grown foods because______A.organic foods can be more expensive but are often no better than conventionally grown foodsB.many organic foods are actually less nutritious than similar conventionally grown foodsC.conventionally grown foods are more readily available than organic foodsD. too many farmers will stop using conventional methods to grow food crops
The word “advocates” in paragraph 1 is closest in meaning to which of the following?A.ProponentsB.MerchantsC.InspectorsD.Consumers
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