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单选题{{B}}第二篇{{/B}} {{B}}Adaptation of Living Things{{/B}} Certain animals and plants develop characteristics that help them cope with their environment better than others of their kind. This natural biological process is called adaptation. Among the superior characteristics developed through adaptation are those that may help in getting food or shelter, in providing protection, and in producing and protecting the young. That results in the evolution of more and more organisms that are better fitted to their environments. Each living thing is adapted to its way of life in a general way, but each is adapted especially to its own distinct class. A plant, for example, depends upon its roots to fix itself firmly and to absorb water and inorganic chemicals. It depends upon its green leaves for using the sun's energy to make food from inorganic chemicals. These are general adaptations, common to most plants. In addition, there are special adaptations that only certain kinds of plants have. Many animals have adaptations that help them escape from their enemies. Some insects are hidden by their body color or shape, and many look like a leaf or a little branch. The coats of deer are colored to mix with the surroundings. Many animals have the ability to remain completely still when an enemy is near. Organisms have a great variety of ways of adapting. They may adapt in their structure, function, and genetics; in their development and production of the young; and in other respects. An organism may create its won environment, as do warm-blooded mammals, which have the ability to adjust body heat exactly to maintain their ideal temperature despite changing weather. Usually adaptations are an advantage, but sometimes an organism is so well adapted to a particular environment that, if conditions change, it finds it difficult or impossible to readapt to the new conditions.
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单选题Which of the following can best replace the title of the passage?
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单选题 下面打3篇短文,每篇短文后有5道题,每道题后面有4个选项。请根据文章的内容,从每题所给的4个选项山选择1个最佳答案。{{B}}第一篇{{/B}} {{B}} "Salty" Rice Plant Boosts Harvests{{/B}} British scientists are breeding a new generation of rice plants that will be able to grow in soil containing salt water. Their work may enable abandoned farms to become productive once more. Tim Flowers and Tony Yeo, from Sussex University's School of Biological Sciences, have spent several years researching how crops, such as rice, could be made to grow in water that has become salty. The pair have recently begun a three-year programme, funded by the Biotechnology and Biological Sciences Research Council, to establish which genes enable some plants to survive salty conditions. The aim is to breed this capability into crops, starting with rice. It is estimated that each year more than 10m hectares (公顷) of agricultural land are lost because salt gets into the soil and stunts (妨碍生长) plants. The problem is caused by several factors. In the tropics, mangroves (红树林) that create swamps (沼泽) and traditionally formed barriers to sea water have been cut down. In the Mediterranean, a series of droughts have caused the water table to drop, allowing sea water to seep (渗透) in. In Latin America, irrigation often causes problems when water is evaporated (蒸发) by the heat, leaving salt deposits behind. Excess salt then enters the plants and prevents them functioning normally. Heavy concentrations of minerals in the plants stop them drawing up the water they need to survive. To overcome these problems, Flowers and Yeo decided to breed rice plants that take in very little salt and store what they do absorb in cells that do not affect the plants' growth. They have started to breed these characteristics into a new rice crop, but it will take about eight harvests before the resulting seeds are ready to be considered for commercial use. Once the characteristics for surviving salty soil are known, Flowers and Yeo will try to breed the appropriate genes into all manners of crops and plants. Land that has been abandoned to nature will then be able to bloom again, providing much needed food in the poorer countries of the world.
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单选题The room is gloomy but tidy.
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单选题Youth hotels provide inexpensive lodging for young people throughout the United States and in other countries.
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单选题That player is {{U}}eternally{{/U}} arguing with the referee. A. desperately B. constantly C. eventually D. extensively
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单选题The girl is {{U}}gazing{{/U}} at herself the mirror.
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单选题We will take your recent illness into {{U}}consideration{{/U}} when marking your exams
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单选题What does NASA plan to do?
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单选题I enjoyed the play it had a clever plot and {{U}}funny{{/U}} dialogues. A. long B. boring C. original D. humorous
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单选题I go to the movies occasionally at the weekends.
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单选题I am {{U}}very{{/U}} sorry for ringing you late last night.
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单选题Yet in one way they are really so fortunate.A. to some extentB. in the wayC. by the wayD. just then
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单选题Norman Blamey is an artist of deep convictions .
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单选题Which of the following best summarizes the main information of the passage?
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单选题It is nearly impossible to conciliate these two disagreeing parties.
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单选题Her treatment of the subject is exhaustive .
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单选题There's nothing at all on this piece of paper. It's completely Ublank/U.
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单选题{{B}}第二篇{{/B}} {{B}} A Phone That Knows You're Busy{{/B}} It's a modern problem: You're too busy to be disturbed by incessant (连续不断的) phone calls so you turn your cellphone off. But if you don't remember to turn it back on when you're less busy, you could miss some important calls. If only the phone knew when it was wise to interrupt you, you wouldn't have to turn it off at all. Instead, it could let calls through when you are not too busy. A bunch of behavior sensors (传感器) and a clever piece of software could do just that, by analyzing your behavior to determine if it's a good time to interrupt you. If built into a phone, the system may decide you're too busy and ask the caller to leave a message or ring back later. James Fogarty and Scott Hudson at Camegie Mellon University in Pennsylvania based their system on tiny microphones, cameras and touch sensors that reveal body language and activity. First they had to study different behaviors to find out which ones strongly predict whether your mind is interrupted. The potential "busyness" signals they focused on included whether the office doors were left open or closed, the time of day, if other people were with the person in question, how close they were to each other, and whether or not the computer was in use. The sensors monitored these and many other factors while four subjects were at work. At random intervals, the subjects rated how interruptible they were on a scale ranging from "highly interruptible" to "highly not-interruptible". Their ratings were then correlated with the various behaviors. "It is a shotgun (随意的) approach: we used all the indicators we could think of and then let statistics find out which were important," says Hudson. The model showed that using the keyboard, and talking on a landline or to someone else in the office correlated most strongly with how interruptible the subjects judged themselves to be. Interestingly, the computer was actually better than people at predicting when someone was too busy to be interrupted. The computer got it right 82 per cent of the time, humans 77 per cent. Fogarty speculates that this might be because people doing the interrupting are inevitably biased towards delivering their message, whereas computers don't care. The first application for Hudson and Fogarty's system is likely to be in an instant messaging system, followed by office phones and cellphones. "There is no technological roadblock (障碍) to it being deployed in a couple of years," says Hudson.
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单选题National forests {{U}}make{{/U}} money for the government through the sale of trees for lumber.
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