Imagine putting a seed in a freezer, waiting 30,000 years, and then taking the seed out and planting it. Do you think a flower would grow?
Amazingly, scientists have just managed to do something very similar. They found the fruit of an ancient plant that had been frozen underground in Siberia — a region covering central and eastern Russia — for about 31,800 years. Using pieces of the fruit, the scientists grew plants in a lab. The new blooms have delicate white petals. They are also the oldest flowering plants that researchers have ever revived from a deep freeze.
“This is like regenerating a dinosaur from tissues of an ancient egg,” said University of California, Los Angeles biologist Jane Shen-Miller.
The plant has a long history. Back when mammoths and woolly rhinoceroses walked the land, an Arctic ground squirrel buried seeds and fruits in an underground chamber near the Kolyma River in northeastern Siberia. The ground became permafrost, a layer of soil that stays frozen for a long time.
Recently, Russian scientists dug out the old squirrel hole and found the plant remains 38 meters below the surface. Back at the lab, the team fed nutrients to tissue from three of the fruits to grow shoots. Then the scientists transferred the shoots to pots filled with soil. The plants produced seeds that could be used to grow even more of them.
It’s important for scientists to know that plant tissues can still be revived after being frozen for a long time. That’s because many researchers are trying to preserve the seeds of modern plants by freezing them and then storing them in giant lockers at various spots around the globe. One such endeavor, an underground facility in Norway, is called the Svalbard Global Seed Vault. It stores hundreds of thousands of frozen seeds. If a plant ever goes extinct, scientists could bring it back by taking its seeds from the Svalbard or other storage lockers.
“No one knows how long they are able to live for, but freezing is basically the format for many plant conservation attempts nowadays.” Shen-Miller said. It’s a good thing that at least some plants are tough enough to survive the experience.
64. How did the fruit originally get underground?
A. It was placed there by an animal.
B. It was trapped there during the ice-age.
C. It was planted there by ancient farmers.
D. It was buried there after the earthquake.
65. Why are scientists interested in this discovery?
A. It helps them learn how plant life has changed in the past 30,000 years.
B. It can help guide future efforts to protect endangered plant-life.
C. It can provide directions for where to look for other ancient plants.
D. It proves that all plant life can survive for thousands of years when frozen.
66. The underlined word “they” in the final paragraph refers to _______.
A. plants B. seeds C. scientists D. storage lockers
67. The purpose of the passage is to _______.
A. discuss a plant conservation effort B. introduce some ancient plants
C. outline some causes of global warming D. describe a scientific research project
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科目:高中英語(yǔ) 來(lái)源:2012-2013學(xué)年安徽省無(wú)為開(kāi)城中學(xué)高二下學(xué)期第二次月考英語(yǔ)卷(帶解析) 題型:閱讀理解
Why do parents have such a difficult time to communicate openly and honestly with their teens? For this, there are many reasons but most of them stem from not being able to properly understand their teens. It is a dangerous gap because parents will have to communicate with their teens about a wide variety of issues during the most important years of their lives. Thus, parents must know how to communicate openly and honestly with their teens.
Here are a few tips to make communication easier between parents and teenagers.
1. Try not to talk down to your teens. Make them feel as if their views really matter, which not only helps your discussions with your teen but bring you closer to him.
2. Imagine what it would be like to be a teen. Try to remember some of the negative feelings you experienced as a teenager and apply it to your teen's situation.
3. Never make negative remarks to your teen about what she has said or done.
4. Remember how much courage it would have taken for your teen to come and talk to you about his personal issues. So listen respectfully.
5. Don't ignore your teen's feelings because it is usually a cry for help. For instance, if your teen is unusually angry, it may be time to spend a bit of quality time with your teen to determine what is wrong and where he is coming from.
It is, therefore, necessary for parents to strive to keep lines of communication open at all times with their teens. Try to remember what it was like to be a teenager and how vulnerable(脆弱的)you felt. Then you will be well on your way to help your teen communicate more openly and honestly.
【小題1】Why don't teens want to talk about their personal issues with their parents?
A.Because they can't respect their parents. |
B.Because they can't understand their parents. |
C.Because their parents won't understand them well. |
D.Because their parents are not honest. |
A.listen respectively | B.treat him seriously |
C.care about his feeling | D.make negative remarks |
A.put down | B.look down upon | C.chat with | D.quarrel with |
A.Causes of generation gap |
B.Relations between teens and parents |
C.Suggestions for parents-children effective communication |
D.Problems with communication between teens and parents |
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科目:高中英語(yǔ) 來(lái)源:2012-2013學(xué)年甘肅武威第六中學(xué)高一下學(xué)期模塊檢測(cè)英語(yǔ)卷(帶解析) 題型:閱讀理解
Imagine when you are sailing an ocean for the first time, you see a big fish swimming near your ship. You might be scared, and worried about whether it will turn over your ship for a meal. In fact, it is not a fish at all, but a gentle giant whale.
Whales are not fishes but mammals (哺乳動(dòng)物). Their body temperature stays the same, and does not change with the temperature of their environment. They breathe air, so they have to come out of the water to get oxygen. Thus, they cannot afford to fall into a sleeping state for too long, since they need to be awake in order to breathe. It is thought that only half of their brains sleep at a time, so that whales are never completely asleep. Females give birth to the young. They have hair. Although they are not covered in hair or fur like many mammals, whales have some bristles (胡子), usually on their heads.
Whales are highly social animals with complex languages and intelligence. They communicate with each other using romantic sounds, called “whale songs”. Being so large and powerful, these sounds are also loud.
Whales are endangered as a result of whaling (捕鯨) from the eleventh century to the twentieth. It has attracted the attention of environmentalists and some measures (措施) have been taken to protect whales.
【小題1】How many aspects show that whales are mammals?
A.One. | B.Two. | C.Three. | D.Four. |
A.whales can breathe in the water |
B.if a whale sleeps too long, it will get drowned |
C.in order to breathe, whales never sleep |
D.whales give birth to the young on the land |
A.By body language. | B.By speaking languages. |
C.By making song-like sounds. | D.By giving off a smell. |
A.Whales are cold-blooded mammals like fishes. |
B.Whales are hunted for food by people. |
C.Whales are very harmful to human beings. |
D.Whales are in danger because of being killed by people. |
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科目:高中英語(yǔ) 來(lái)源:2012-2013學(xué)年江蘇省無(wú)錫一中高一下學(xué)期期中考試英語(yǔ)卷(帶解析) 題型:閱讀理解
Family Vs Technology
Modern technology certainly changes family behavior, but does it really damage family life as many people fear? Not necessarily, says Dr. Silva, a professor in Sociology(社會(huì)學(xué)) at the Open University, she also argues it is wrong to assume technology erodes(腐蝕,侵蝕) the quality of family life.
“There is the idea that technology has an influence on the family and the family suffers. My take is quite different,” she explains. “Technological change happens because people’s lives change. And it is people’s choices of how to live that creates processes of innovation(革新) as well. The family has a role like the economy or like technology itself in changing the world. The imagination is important in driving the things technologists want to find for our daily lives. People desire to see nature as it is, so color television comes about,” she says.
In another case, the increase in working mothers helped create a market for labor-saving kitchen equipment. “The time that women have to shop every day for food is no longer available so there is a need to have a refrigerator for food storage,” says Dr. Silva. “The need to cook that food more easily and quickly, means you have developments in cooking technology like the microwave oven(微波爐). The microwave oven already existed because it was developed for the navy during World War Two but it wasn’t used in ordinary families until the early 1980s.
“Technologies for housework were as important as those for work itself,” she says, “So washing machines, refrigerators and microwave ovens are terribly important. We couldn’t imagine what life would be like if we didn’t have them.” Technological changes in the kitchen have played an important role in the changes of family behavior, creating a new social focus in the home.
“With advanced technology, you can feed the family in an easier manner. People can do housework with less difficulty. But that doesn’t mean that family practices are not important — it’s just a different way of doing things.”
【小題1】What is Dr. Silva’s attitude towards the effect that technology has on family life?
A.Worried. | B.Optimistic(樂(lè)觀的). |
C.Puzzled. | D.Uncertain. |
A.People’s love for nature. |
B.Great changes in people’s way of life. |
C.People’s desire to change the world. |
D.The wonderful imagination in inventing things. |
A.The microwave oven was first used by working mothers. |
B.People cook less because of modern kitchen equipment. |
C.Technology has little effect on the changes of family behavior. |
D.People need less skill to do housework due to advanced technology. |
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科目:高中英語(yǔ) 來(lái)源:2011-2012學(xué)年北京西城區(qū)(南區(qū))高二下學(xué)期期末質(zhì)量檢測(cè)英語(yǔ)試卷(帶解析) 題型:閱讀理解
I once did a year of voluntary service in a residential home for people with learning disabilities. It was set in an English village deep in the countryside, quite different from my home in Sweden. One of my fellow volunteers, a girl from Tanzania, seemed a little unhappy, so I asked what the problem was. She told me she had a friend back home who had financial difficulties and maybe it was impossible for her to complete her university courses.
So this friend of mine had sent all her money to Tanzania to support her friend! This meant that she didn't have much food to eat and no money to go anywhere outside the village.
I was so touched and I felt I had to do something. So, during my next trip to one of the nearby towns I walked into a shop. I didn’t have much money left myself but I thought I'd buy her an extra box of chocolate we both liked and some rice. I started talking to the woman(also a volunteer)working in the shop and eventually told her about my friend.
The woman looked at me, amazed. “Does she eat pasta?” she asked. “Yes,” I replied. She immediately started loading a bag with pasta, cookies, and other things until the bag was full. “Give her this for me. It’s my treat!’’ I couldn’t believe it but accepted with happiness. As I left the shop to go home with my unexpected bag of food, I asked the woman her name. “Just Gloria,” she said.
Imagine my friend’s face when I arranged the gifts on my kitchen table and fetched her from her room to see! I had never seen her so happy! A few weeks later she found Gloria in the shop and thanked her in person.
These two extraordinary women really showed me what true kindness and compassion(同情)are, and the impression will stay with me for the rest of my life!
【小題1】The underlined word “it” in Paragraph 1 probably refers to .
A.the shop |
B.the writer's home |
C.the residential home |
D.a(chǎn) year of voluntary service |
A.Because she had to stop her voluntary work. |
B.Because she had no money to buy food or other things. |
C.Because she had spent all her money on food and clothes. |
D.Because her friend in Tanzania maybe had to quit school for lack of money. |
A.Because the writer was a volunteer. |
B.Because they lived in the same room. |
C.Because the writer was moved by her kind act. |
D.Because the writer didn’t wish she went hungry. |
A.the writer was from England |
B.the writer was a university student from Tanzania |
C.Gloria was from Sweden and was very kind to the writer |
D.the writer volunteered to help people with learning disabilities |
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科目:高中英語(yǔ) 來(lái)源:2012屆江西省洛市中學(xué)高三第四次月考英語(yǔ)卷 題型:閱讀理解
Imagine a boy from a small village in East Africa, He from a very early age has been looking after cattle. At twelve years old he knows more about cattle than most of you. However, he has never been to school. Has this boy ever had any education?
Education is discovering about ourselves and about the people and things around us. All the people who care about us — our parents, brothers, sisters, friends — are our teachers. In fact, we learn something from everyone we meet. We start learning on the day we are born, not on the first day" we go to school. Every day we have new experiences, like finding a bird's nest, discovering a new street in our neighborhood, making friends with someone we didn't like before. New experiences are even more fun when we share them with other people.
Encouragement from the people around us enables us to explore things as much as possible. As we grow up, we begin to find out what we are capable of doing. You may be good at cooking, or singing or playing football. You find this out by doing these things. Just thinking about cooking doesn't tell you if you are good at it.
We learn so much just living from day to day. So why is school important? Of course you can learn some things better at home than at school, like how to do the shopping, and how to help old or disabled people who can' t do everything for themselves. At school, teachers help us to read and write. With their guidance, we begin to see things in different ways.
【小題1】 The writer takes the African boy as an example to show that _______.
A.African children are very poor |
B.some children are unlucky |
C.education takes many ways |
D.schools are of great importance |
A.we have to learn from the people around us |
B.school is not important at all |
C.only the people caring for us can teach us |
D.education takes place everywhere |
A.the encouragement of people around | B.the teachings of those he or she meets |
C.thinking of it when growing up | D.trying practicing it |
A.school is not so important as our living places |
B.school enables us to understand the world in other ways |
C.school teaches us something useless at home |
D.school cannot prepare us for our daily lives |
A.everyone gets education from the day he or she is born |
B.different education trains different classes of people |
C.school is absolutely necessary if one wants to understand the world |
D.everyone will find out what he or she is good at |
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