As skies are filled with millions of migrating(迁徙)birds, European scientists sa
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As skies are filled with millions of migrating(迁徙)birds, European scientists say the seasonal wonder appears to be strange: The fatter the bird, the better it flies.
The results of their study led to a theory opposite to a central one of aerodynamics(空气动力学), which says that the power needed to fly increases with weight.
For birds, obviously, the cost of flying with heavy fat is much smaller than we used to think. Researchers found that red knot wading birds double their normal body weight of 100 grams before making their twice-a-year nonstop flight between the British Isles and the Russian Arctic. Distance: 5, 000 kilometers.
Another study in the magazine Nature measured the advantage of flying in an aerodynamic group which allows birds to save energy by flying smoothly and quietly in the lead bird’s air stream.
Flying in groups, their heart rates were 14.5 percent lower than flying alone, according to Henri, a French scientist. The findings help explain how birds complete difficult migrations. Researchers had thought that thinner, stronger birds would have the best chance to survive.
The first study suggests that building up fat to be burnt as fuel during the migration is worth more than the energy it takes to carry the additional weight.
In the study, researchers said their team studied the birds flown at different body weights during 28 simulated(模拟的)flights. They forced a small amount of special water into the birds’ bodies so that they could measure the amount of energy burnt during the flight.
60.A red knot wading bird of 100 grams will probably weigh_____before making its nonstop migrating flight.
A.50 grams B.100 grams C.150 grams D.200 grams
61.During their migrating flight, red knot wading birds can save energy by flying_______.
A.separately B.alone C.in groups D.in pairs
62.A_______red not wading bird has a better chance to survive during its migrating flight.
A.stronger B.weaker C.thinner D.fatter
63.The best title for this passage may probably be________.
A.Birds Thin Down For Journey B.Birds Fatten Up For Journey
C.How Birds Build Up Fat For Journey D.How Birds Burn Energy For Journey |
答案
60--63 DCDB |
解析
60．解析：这是一道计算题。根据第三段中的Researchers found that red knot wading birds double their normal body weight of 100 grams before making their twice-a-year nonstop flight between the British Isles and the Russian Arctic.可计算出在进行不停顿的迁徙飞行，一只red knot wading bird可能重200克。double their normal body weight of 100 grams表示“它们正常体重100克的两倍”，即200克。
61．解析：这是一道细节题。第四段中的Another study in the magazine Nature measured the advantage of flying in an aerodynamic group which allows birds to save energy by flying smoothly and quietly in the lead bird’s air stream.说明red knot wading birds以一群鸟一起飞行的方式进行飞行时能够节省能量。
62．解析：这是一道细节题。从第五段中的Researchers had thought that thinner, stronger birds would have the best chance to survive.可以看出，比较肥胖的red knot wading birds在迁徙飞行中更有机会存活。句子的谓语是虚拟语气，说明研究者原先认为越瘦越强壮的red knot wading birds存活的机会越大，而实际情况与此相反。
63．解析：这是一道标题选择题。这篇短文报道了对red knot wading birds迁徙飞行的研究，研究表明因为red knot wading birds在迁徙过程中消耗大量能量，所以比较肥胖的red knot wading birds越有在迁徙飞行中存活的机会，因此这篇短文的题目应是：Birds Fatten Up For Journey。 |
举一反三
The coyote(丛林狼)that clever animal of wide-open spaces,has come to the nation’s captial.In fact ,coyotes have spread to every corner of the United States,changing their behaviors to fit new environments and causing researchers to deal with a troublesome new kind of creature:the city coyote.
The coyote originally lived in the middle of the continent.One of its most obvious characters is its smartness, which has made the animal a notorious（臭名昭著的）pest.Hunters trapped,shot and poisoned more than a million coyotes in the 1900s.It’s still one of America’s most hunted animals. Yet the coyote has survived.How has the coyote shown this extraordinary ability? “I guess if you wanted to use one word,it’d be ‘plasticity’. ”says Erie Gese,an expert at Utah State University. Coyotes can live alone, in pairs, or in large packs like wolves,hunt at night or during the day , occupy a small region or an area up to 40 square miles;and live on all sorts of food,from lizards（蜥蜴）and shoes, to ants and melons.
Unbelievably people helped coyotes increase when they killed most of the wolves in the United States. The spreading of coyotes into city areas,though.is recent.They travel at night,crossing sidewalks and bridges.running along roads and ducking into culverts （钻入涵洞）and underpassces .No one knows why coyotes are moving into cities, but experts explain that cleverer, more human-tolerant（不怕人的）coyotes are teaching urban survival skills to new generations.
Occasionally. coyotes might attack human beings. There have been about 160 attacks on people in recent years Therefore, people have been consistently told not to feed coyotes or leave pet food unsecured. That ,plus a large trapping program in the neighborhood, has cut down on the coyote population.
63.The underlined word “plasticity”in Paragraph 2 refers to____________.
A.the ability to fit the environment B.notorious smartness
C.hunting ability D.being human-tolerant
64.The aim of the passage is to_____________.
A.tell people how to fight against coyotes
B.tell us why the coyote is the most hunted animal
C.supply the reason why the coyote is a kind of motorious pest
D.explain how the coyote has spread to and survived in cities
65.According to the passage, coyotes__________.
A.originally lived in the west of the continent
B.sleep during the day but look for food at night
C.are teaching survival skills to their younger generations
D.suffered a population decrease because people killed wolves
66.According to the passage,to cut down on the coyote population, people are advised to_______.
A.leave pet food secured B.keep coyotes in small regions
C.force coyotes to live alone D.avoid using trapping programs |
The discovery of a dwarfed (矮个的)”human being” who lived in Flores .Indonesia, up to 18,000 years ago is changing the way we think about the human family .This “Flores Human”was three foot tall and her brain was smaller than that of the average chimp (黑猩猩),yet she and her relatives apparently lived fully human lives.They seem to have made tools ,worked together to find food and cook it,and perhaps even buried their dead with ceremony.
It was a major surprise to find tools associated with the new human family member .The tools are like those formerly seen only with European fossils (化石)from our own species;Homo sapiens (智人)；and the oldest of them were made 94,000 years ago .Homo sapiens is thought to have arrived in the island about 40,000 years ago ,much too late to be responsible for the tools .If this tiny human made the tools ,them the inside structure (结构)of its brain must have been more like our own than a chimp’s ,despite being just a third the size of ours.
This “new human” was suspected to be a dwarfed branch of Homo erectus (直立人).When creatures are separated in regions with rare resources but few enemies,being big is a disadvantage, and evolution tends to shrink them, a process known as island dwarfing.Could natural selection make a human smaller while keeping — even improving — mental ability ?Quite possibly, believes Christopher Wills of the University of California.
Has the “Flores Human” even shown the ability of language? “I find it difficult to imagine that people could make tools，use fire ,and kill large animals without fairly advanced communication.” Wills says .Did “Flores Human” possess the basic components of human culture — such as the burying of the dead with ceremony ? Emiliano Bruner of the Italian Institute points out that Indonesia’s hot, wet environment is bad for fossilization.It is reasonable to assume , he says ,that the 18,000-year-old bones of the most complete Flores woman were well-preserved because she was buried with special care.
67.According to the passage , “Flores Human”______.
A.lived a partly human life B.was a branch of Homo sapiens
C.used tools before Homo sapiens arrived D.had a brain as a common chimp’s
68.The underlined part “this tiny human”in Paragraph 2 refers to _______.
A.a chimp . B.Flores Human C.Homo sapiens D.Homo erectus
69.This passage mainly talks about______.
A.the tools made by “Flores Human” B.the language used by “Flores Human”
C.the evolution of “Flores Human” D. the major surprising findings about “Flores Human”
70.According to the passage ,it is believed that “Flores Human”_______.
A.was dwarfed by its enemies B.could use language
C.left a lot of fossils in hot and wet enviromentD.reached Flores 40,000 years ago |
An ichthyologist is a scientist who studies fish. Most people who do this job say they love their work because it is very rewarding and varied. They work not only inside a laboratory, but also out in the field. Fieldwork includes traveling to rivers, oceans and lakes in order to collect information and specimens（样本）, Reading, writing and speaking are also very important to the job. Fish scientists need to read the research of other scientists. They must he able to write up their own research clearly so that others can follow it. They also need to be able to give lectures about their findings, so that they can spread knowledge.
Ichthyologists who wish to specialize can choose any one of three areas of study. The first area is aquaculture (水产养殖). This involves the study and practice of fish farming and management. Because it is a rather new study, there are very few job opportunities available. However, as there is so much to discover, many see it as an exciting area for a new ichthyologist to enter. The second area is fisheries science, which means working with a team of scientists to find out more about different fish species. The third area is about the protection of natural fish populations. This is very important today, given that many fish species are in danger of dying out because of the actions of humans.
To become a successful fish scientist, you need to have a curious mind and be able to work on your own. You also need to be able to handle equipment and perform experiments; but most importantly, you must love fish. To become an ichthyologist, you will need to train at a university to pass a Bachelor of Science degree. For this, you will need to be good at mathematics, physical science and biology. Then, you will need to study for another year to complete an honours degree in ichthyology. This honours degree contains coursework about all aspects of fish. You also need to complete a research paper.
68. What makes the jobs of ichthyologists so varied?
A. They study fish habits and collect information.
B. They have to study science and mathematics.
C. They work in fields as well as in laboratories.
D. They read research papers written by others.
69. Which of the following statements is NOT true according to the passage?
A. An ichthyologist has an interesting and varied profession.
B. Aquaculture is the study of fish protection.
C. The life of an ichthyologist can involve lots of travel.
D. A fish scientist needs to be independent and curious about things.
70. Who is most likely to become an ichthyologist?
A. Tom, because he likes fishing and outdoor sports.
B. Jack, because he likes to travel and read adventure books.
C. Jenny, because she likes science, mathematics and reading about dinosaurs.
D. Jane, because she likes mathematics, science, biology and searching rock-pools.
71. The passage is probably written for .
A. university students B. science researchers
C. fisheries experts D. fish farmers |
When a storm is coming, most people leave the area as quickly ad possible and head for safety. But there are a few people who will get into their cars and go straight for the center of the storm. These people are willing to risk(冒…危险)being killed by floods or 100-kilometer-an-hour winds for the excitement of watching the storm close up.
“Storm chasing(追逐)” is becoming an increasingly popular hobby(喜好), especially in the Midwest of the United States, where there are frequent storms between March and July. A storm chaser begins the day by checking the Internet for the latest weather reports, and then drives up to 1,000 kilometers to where the storm will be and waits for it to develop.
Although anyone can do it , storm chasing is extremely dangerous. The power of a big storm can throw a cow into the air or destroy a whole house in seconds. Storm chasers are also often hurt in accidents caused by driving in a heavy rain. If you are a beginner, it is much safer to join a group for storm-chasing vacations during the storm season.
Even then, storm chasing is not all adventure and excitement . “Storm chasing is 95% driving,” says Daniel Lynch, who spends most of his summer storm-chasing. “Sometimes you can sit around for hours waiting for something to happen, and all you get is blue sky and a few light showers.”
However, for storm chasers, it is all worth it. “When you get close to a storm, it is the most exciting sight you will ever see in your life,” says Jasper Morley. “Every storm is an example of the power of nature, It is the greatest show on Earth.”
56. For storm chasing, the first thing storm chasers do is to .
A. head straight for the center of the storm B. get into the car for safety
C. wait patiently for the storm to develop D. collect information about a coming storm
57. Beginners of storm chasing are advised .
A. not to drive in a heavy rain B. to do it in an organized way
C. not to get too close to a storm D. to spend more time on it in summer
58. By saying “it is all worth it” in the last paragraph, the author means that .
A. storm chasing costs a lot of money B. storm chasing is worth hours of waiting
C. efforts in storm chasing are well paid D. a storm presents the greatest show on Earth
59. What can we learn from the text?
A. Sometimes storm chasers get nothing but disappointment
B. Many storm chasers get killed in the storms.
C. Storm chasing is becoming popular around the world.
D. Storm chasing is only fit for young people. |
Lions are opportunists. They prefer to eat without having to do too much work. When resting in the shade, they are also watching the sky to see what is flying by, and even in the heat of the day they will suddenly start up and run a mile across the plains to find out what is going on. If another animal has made a kill, they will drive it off and take the kill for themselves. A grown lion can easily eat 60 pounds of meat at a single feeding. Often they eat until it seems painful for them to lie down.
The lionesses (母狮) , being thinner and faster, are better hunters (猎手) than the males (雄狮). But the males don’t mind. After the kill they move in and take the test share.
Most kills are made at night or just before daybreak. We have seen many, many daylight attempts but only ten kills. Roughly, It’s about twenty daytime attempts for one kill.
When lions are hiding for an attack by a water hole, they wait patiently and can charge at any second. The kill is the exciting moment in the day-to-day life of the lion, since these great animals spend most of their time, about 20 hours a day, sleeping and resting.
Lions are social cats, and when they are having a rest, they love to touch each other. After drinking at a water hole, a lioness rests her head on another’s back. When walking, young lions often touch faces with older ones, an act of close ties among members of the group.
64. By describing lions as “opportunists” in the first paragraph, the author means to say that lions .
A. are cruel animals B. are clever animals
C. like to take advantage of other animals D. like to take every chance to eat
65. According to the text, which of the following is true?
A. Lions make most kills in the daytime.
B. Males care more about eating than active killing.
C. Lions are curious about things happening around them.
D. It doesn’t take lions too much time to make a kill.
66. How can we know that lions are social animals?
A. They depend on each other. B. They look after each other well.
C. They readily share what they have. D. They enjoy each other’s company.
67. What would be the best title for the text?
A. Powerful Lions B. Lions at Work and Play
C. Lions, Social Cats D. Lions, Skilled Hunters |
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