题目
题型:不详难度:来源:
Robert Wayne of the University of California, Los Angeles, and Jennifer Leonard of the Smithsonian Institute, used DNA material—some of it unearthed by miners in Alaska—to conclude that today’s domestic dog originated in Asia and accompanied the first humans to the New World about 10,000 to 15,000 years ago. Wayne suggests that man’s best friend may have enabled the tough journey from Asia into North America. “Dogs may have been the reason people made it across the land bridge,” said Wayne. “They can pull things, carry things, defend you from fierce animals, and they’re useful to eat.”
Researchers have agreed that today’s dog is the result of the domestication(驯化) of wolves thousands of years ago. Before this recent study, a common thought about the precise origin of North America’s domestic dog was that Natives domesticated local wolves, the descendents(后代) of which now live with people in Alaska, Canada, and the Lower 48.
Dog remains from a Fairbanks-area gold mine helped the scientists reach their conclusion. Leonard, an evolutionary biologist, collected DNA from 11 bones of ancient dogs that were locked in permafrost(永冻层) until Fairbanks miners uncovered them in the 1920s. The miners donated the preserved bones to the American Museum of Natural History in New York City, where they remained untouched for more than 70 years. After borrowing the bones from the museum, Leonard and her colleagues used radiocarbon techniques to find the age of the Alaska dogs. They found the dogs all lived between the years of 1450 and 1675 A.D., before Vitus Bering and Aleksey Chirikov who were the first known Europeans to view Alaska in 1741. The bones of dogs that wandered the Fairbanks area centuries ago should therefore be the remains of “pure native American dogs,” Leonard said. The DNA of the Fairbanks dogs would also expose whether they were the descendents of wolves from North America.
Along with the Fairbanks samples, the researchers collected DNA from bones of 37 dog specimens(标本) from Mexico, Peru, and Bolivia that existed before the arrival of Columbus. In the case of both the Alaska dogs and the dogs from Latin America, the researchers found that they shared the most genetic material with gray wolves of Europe and Asia. This supports the idea of domestic dogs entering the New World with the first human explorers who wandered east over the land bridge.
Leonard and Wayne’s study suggests that dogs joined the first humans that made the adventure across the Bering Land Bridge to slowly populate the Americas. Wayne thinks the dogs that made the trip must have provided some excellent service to their human companions or they would not have been brought along. “Dogs must have been useful because they were expensive to keep,” Wayne said. “They didn’t feed on mice; they fed on meat, which was a very guarded resource.”
小题1: The underlined word “remains” is closed in meaning to ______.
A.leftover food | B.animal waste |
C.dead bodies | D.living environment |
A.ancient dogs entered North America between 1450 and 1675 AD |
B.the 11 bones of ancient dogs are not from native American dogs |
C.the bones discovered by the gold miners were from North American wolves |
D.the bones studied were not from dogs brought into North America by Europeans |
A.Native Americans domesticated local wolves into dogs. |
B.Scientists discovered some ancient dog remains in 1920s. |
C.Latin America’s dogs are different from North America’s in genes. |
D.Ancient dogs entered North America across the Bering Land Bridge. |
A.dogs fed on mice | B.dogs were easy to keep |
C.dogs helped protect their resources | D.dogs could provide excellent service |
A.the origin of the North American dogs |
B.the DNA study of ancient dogs in America |
C.the reasons why early people entered America |
D.the difference between Asian and American dogs |
答案
小题1:C
小题2:D
小题3:D
小题4:D
小题5:A
解析
试题分析:本文是科普性文章。说明了在几千年前狗陪同人们一起跨过白令大陆桥进入北美大陆,并且在此繁殖起来。而通过检测发掘出的狗骨头的DNA也证实了这一点。
小题1:C 词意猜测题。根据第四段第二句话“Leonard, an evolutionary biologist, collected DNA from 11 bones of ancient dogs that were locked in permafrost(永冻层)”说明是在冰冻层发现的狗的骨头,所以remain应该是尸体。C选项正确。
小题2:D细节题。根据“They found the dogs all lived between the years of 1450 and 1675 A.D before Vitus Bering and Aleksey Chirikov who were the first known Europeans to view Alaska in 1741..”判断可知被研究的骨头不是欧洲人带到北美来的狗的骨头。所以D项正确。
小题3:D细节题。根据第一段“When people first walked across the Bering Land Bridge thousands of years ago, dogs were by their sides, according to a study published in the journal Science.”所以D选项正确。
小题4:D 细节题。根据第二段“Wayne suggests that man’s best friend may have enabled the tough journey from Asia into North America. “Dogs may have been the reason people made it across the land bridge,” said Wayne. “They can pull things, carry things, defend you from fierce animals, and they’re useful to eat.”这些都说明了人们之所以带着狗,是因为它们能为人们提供服务,由用处。所以D正确。
小题5:A推理题。文章第一段提到狗和人们一同跨过the Bering Land Bridge,第二三四五段研究狗的DNA“ to conclude that today’s domestic dog originated in Asia”,“Researchers have agreed that today’s dog is the result of the domestication(驯化) of wolves thousands of years ago”所以文章中心是谈论狗的起源。
核心考点
试题【When people first walked across the Bering Land Bridge thousands of years ago, d】;主要考察你对题材分类等知识点的理解。[详细]
举一反三
Activities in Among the Boys are in agreement with the best practices in the prevention of high-risk behavior. First, community-based youth development programs are considered important parts of a comprehensive prevention method, particularly in high-risk neighborhoods. Second, compensatory(补偿) education that targets at risk youth for academic failure is also considered an effective prevention method. Third, interventions(介入) aimed at improving youth’s moral reasoning, social problem-solving, and thinking skills are reported to be effective methods for reducing violence in high-risk populations, especially when carried out with elementary school-aged boys. Finally, Among the Boys has an adapted tutoring part, considered an effective prevention tool. Tutoring is typically a one-to-one match between a tutor and a youth, but Among the Boys employs what is referred to as “group tutoring.” Among the Boys makes up for its high student-tutor ratio(比例) with quality and quantity of time, as the program meets after school, on Saturdays, and all day during the summer, and is staffed primarily by males, an unusual quality among educational programs.
Among the Boys is rare and successful form of grassroots program, and represents the dream of a successful male who grew up in the Highland Park neighborhood and has returned to make a valuable contribution to his community.
小题1:Which of the following most accurately describes the organization of the second paragraph?
A.A theory is presented and proved with data. |
B.A statement is made and supported with examples. |
C.A problem is put forward and solutions are suggested |
D.A situation is described and a prediction is provided |
A.Art programs can promote painting but cannot prevent school failure. |
B.Social problem-solving skills are not important for high school-age youth. |
C.Most educational programs have some female staff members. |
D.Teamwork produces better paintings than does independent work. |
A.Among the Boys employs a traditional tutoring model |
B.tutoring is effective only with elementary school-age boys |
C.tutoring prevents the youth’s attention from wandering off |
D.increased hours with a group can be as effective as a one-to-one tutoring relationship |
A.sought contributions to make his program successful |
B.designed the program for the same neighborhood in which he grew up |
C.is seeking reelection for the Highland Park community school board |
D.was a successful graduate of Among the Boys when he was a youth |
A.forgiving | B.doubtful | C.praising | D.ignorant |
Last week Jay McCarroll and The HSUS (The Humane Society of the United States) made a bold fur-free statement on the runway, marking a new chapter for the fashion industry and animal protection. The encouraging response to McCarroll’s show confirmed that change is happening in fashion.McCarroll has good reasons for rejecting fur. Each year, tens of millions of amimals, including dogs and cats, needlessly suffer and die to fuel the fur industry. But what did Jay McCarroll use in place of fur?“I have patchwork pieces that contain all sorts of combinations of fabrics. The rest is cotton, nylon, polyester…you name it. I even have some stuff made out of bamboo / cotton blend. Anything but fur and leather,”he told Fashion Wire Daily.
“So many people want to protect animals and live their lives without causing unnecessary cruelty. More than two thirds of Americans have pets, and we share a bond with animals every day. Saying no to fur can help millions of animals, and we want to show our respect to leading designers like Jay who embrace compassion(同情) as the fashion,”said Michael Markarian, executive vice president of The HSUS.“It is great to see leaders in the fashion industry recognizing that the animals need their fur more than we do.”
小题1:Which of the following is true about Jay McCarroll?
A.He is a famous fashion designer. |
B.He is the executive vice president of the HSUS. |
C.He is an editor of Fashion Wire Daily. |
D.He is the head of an animal protection organization. |
A.A new unit of a book. | B.The beginning of a new trend. |
C.The latest issue of a magazine. | D.A newly established organization. |
A.Polyester. | B.Bamboo. | C.Leather. | D.Patchwork pieces. |
A.Human beings depend emotionally on animals. |
B.Fashion can go hand in hand with compassion for life. |
C.Fur is more effective than bamboo/cotton blend for clothing. |
D.Fur is more expensive than other materials for fashion designers. |
“Rest, relaxation, and stress reduction are very important for people’s well-being and health. This can be accomplished through daily activities, such as exercise and meditation, but vacation is an important part of this as well,” said primary care physician Natasha Withers from One Medical Group in New York. Withers lists a decreased risk of heart disease and improved reaction time as some of the benefits from taking some time off. “We also know that the mind is very powerful and can help with healing, so a rested, relaxed mind is able to help the body heal better,” said Withers.
Psychologists confirm the value of vacations for the mind. “The impact that taking a vacation has on one’s mental health is great,” said Francine Lederer, a clinical psychologist in Los Angeles who specializes in stress and relationship management. “Most people have better life perspective and are more motivated to achieve their goals after a vacation, even if it is a 24- hour time-out.” The trips could be good for their health, good for their family and good for their businesses.
The online travel agency Expedia conducted a survey about vacation time in 2010, and according to their data the average American earned 18 vacation days一but only used 14 of them. France topped the list, with the average worker earning 37 vacation days and using all but two of them. Americans’ responses may not be surprising in a culture where long hours on the job often are valued, but that’s not always good for the individual, the family or the employer.
Psychologists have also found that people who don’t take enough time to relax may find it harder to relax in the future. “Without time and opportunity to do this, the nerve connections that produce feelings of calm and peacefulness become weaker, making it actually more difficult to shift into less-stressed states,” Mulhem said.
小题1:How did the author introduce the topic of the text?
A.By making comparisons. | B.By giving an example. |
C.By raising questions. | D.By providing data. |
A.dislike family gatherings |
B.have the shortest vacation |
C.enjoy as many vacations as the French |
D.think much of spending long hours on the job |
A.One should never wait to relax. |
B.Work and rest go against each other. |
C.Time and opportunity wait for no man. |
D.A relaxed mind determines everything. |
There are different kinds of pollutants, each of which comes from different sources. It is necessary to identify the source of pollution, in order to make a policy to eliminate them.
Different products, processes and activities of our industrialized world together form the major source of pollution. The forms of pollution can be mainly divided into three kinds—solid, liquid and gas.
These pollutions have greatly damaged our planet and continue to do so. In fact, pollution is threatening our existence. The whole ecological balance of the earth is changing. Massive destruction of environment has brought about negative effects and even posed a great threat to man’s existence.
We must face the situation that exists and take action to solve our environmental problems. For instance, new laws must be passed to place strict control over industrial pollution, the public must receive the education about the danger of pollution and so on.
The earth is our home and we have the duty to take care of it for ourselves and our later generation. Fortunately, more and more people have realized these problems. Measures have been taken to deal with these situations by the government. Laws have been passed to stop pollution, I hope the problems will be solved in the near future and our home will become better and better.
小题1: How many examples of environmental problems are given in the first paragraph?
A.2 | B.3 | C.4 | D.5 |
A.In all there are three kinds of pollution |
B.If people continue to pollute our planet, there will be no trees. |
C.Industrial pollution has been completely controlled. |
D.Laws have been passed to stop pollution and protect our environment. |
A.2 | B.3 | C.5 | D.6 |
A.despair | B.negative | C.optimistic | D.hopeless |
小题1:Which is the topic for the passage?
A.Traditional Education |
B.Open Education |
C.The Students Are Human Beings First |
D.Two Kinds of Different Education |
A.The students are human beings first, and students second. |
B.The students should be responsible for what they do. |
C.The students’ ideas and feelings are very important. |
D.The teachers should allow the students to do what they want to do. |
A.they should praise the students all the time |
B.they should tell the students what to do all the time |
C.the students should know much about the world |
D.the students should learn much about the world from their teachers |
A.students needn’t study as hard as they did before |
B.students can learn more about the world in open education |
C.most of the teachers don’t agree with the idea of open education |
D.most of the students prefer traditional education to open education |
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