Scientists think they have the answer to a puzzle that confused even Charles Darwin： How flowers evolved and spread to become the most important plants on earth．
Flowering plants, or angiosperms (被子植物), make up about 90% of all living plant species,but how they did this has been a mystery. New research suggests it is due to genome (基因组) size．
Hundreds of millions of years ago,the earth was dominated by ferns (蕨类)and conifers(针叶树) - they were the main plants on the earth． Then, about 150 million years ago， the first flowering plants appeared on earth. They quickly spread to all parts of the world．
Why angiosperms were successful and diverse on earth has been debated for centuries.Charles Darwin himself called it a "mystery", fearing this apparent sudden change might challenge his theory of evolution．
Kevin Simonin from San Francisco State University in California US and other researchers analyzed data held by the Royal Botanic Gardens, Kew， on the genome size of hundreds of plants, including flowering plants, gymnosperms (a group of plants including conifers) and ferns. They then compared genome size with anatomical (结构上的) features. This provides "strong evidence" that the success and rapid spread of flowering plants around the world is due to "genome downsizing"．
By reducing the size of the genome, which is contained within the nucleus (核) of the cell, plants can build smaller cells. The researchers say genome-downsizing happened only in the angiosperms, and this was "a necessary condition for rapid growth rates among land plants"．
1.What do we know about angiosperms？ ______
A.They are superior in number among all living plant species．
B.They controlled the earth for hundreds of millions of years．
C.They challenge Charles Darwin's theory．
D.They are extinct plants in the world．
2.It can be implied that ______ ．
A.Simonin works in the Royal Botanic Gardens Kew
B.Simonin is probably an American biologist
C.Darwin was confident of his theory of evolution
D.Darwin succeeded in figuring out the flower evolution
3.What contributed to the success and diversity of angiosperms？ ______
A.The weaker ferns and conifer．
B.The larger nucleus．
C.The stronger cell．
D.The smaller genome．
4.What can be a suitable title of this passage？ ______
A.Why were gymnosperms successful on earth？
B.What puzzle confused even Charles Darwin？
C.Why angiosperms dominated the earth？
D.When angiosperms outnumbered conifers and Ferns？
高三英语阅读理解中等难度题
Scientists think they have the answer to a puzzle that confused even Charles Darwin： How flowers evolved and spread to become the most important plants on earth．
Flowering plants, or angiosperms (被子植物), make up about 90% of all living plant species,but how they did this has been a mystery. New research suggests it is due to genome (基因组) size．
Hundreds of millions of years ago,the earth was dominated by ferns (蕨类)and conifers(针叶树) - they were the main plants on the earth． Then, about 150 million years ago， the first flowering plants appeared on earth. They quickly spread to all parts of the world．
Why angiosperms were successful and diverse on earth has been debated for centuries.Charles Darwin himself called it a "mystery", fearing this apparent sudden change might challenge his theory of evolution．
Kevin Simonin from San Francisco State University in California US and other researchers analyzed data held by the Royal Botanic Gardens, Kew， on the genome size of hundreds of plants, including flowering plants, gymnosperms (a group of plants including conifers) and ferns. They then compared genome size with anatomical (结构上的) features. This provides "strong evidence" that the success and rapid spread of flowering plants around the world is due to "genome downsizing"．
By reducing the size of the genome, which is contained within the nucleus (核) of the cell, plants can build smaller cells. The researchers say genome-downsizing happened only in the angiosperms, and this was "a necessary condition for rapid growth rates among land plants"．
1.What do we know about angiosperms？ ______
A.They are superior in number among all living plant species．
B.They controlled the earth for hundreds of millions of years．
C.They challenge Charles Darwin's theory．
D.They are extinct plants in the world．
2.It can be implied that ______ ．
A.Simonin works in the Royal Botanic Gardens Kew
B.Simonin is probably an American biologist
C.Darwin was confident of his theory of evolution
D.Darwin succeeded in figuring out the flower evolution
3.What contributed to the success and diversity of angiosperms？ ______
A.The weaker ferns and conifer．
B.The larger nucleus．
C.The stronger cell．
D.The smaller genome．
4.What can be a suitable title of this passage？ ______
A.Why were gymnosperms successful on earth？
B.What puzzle confused even Charles Darwin？
C.Why angiosperms dominated the earth？
D.When angiosperms outnumbered conifers and Ferns？
高三英语阅读理解中等难度题查看答案及解析
Just when scientists think they have discovered and recorded every species of insect that crawls the earth they find something new. Earlier this month, Peter Jager, the head of Frankfurt’s Senckenberg Research Institute reported the discovery of a unique eyeless spider.
The creature that has a leg span (跨度) of six centimeters and a body size of just twelve millimeters was found in a cave inside the tiny nation of Laos, in Southeast Asia. It was identified as a member of the Huntsman spider, a large family that consists of 1100 species. However, the other members of the family all have eyes. The spider is the first one that has no eyes. They believe that the kind of spider has adapted to the fact that they do not really need the eyes to such a degree that they have dispensed with them altogether.
But they are not the only creature to have done that. Over the years, scientists have discovered completely blind cave fish, and even a freshwater crab, which happens to live in the same cave as this eyeless spider!
Surrounded by Burma and China on the northwest, Vietnam on the east, Cambodia on the south and Thailand on the west, the landlocked nation of Laos is filled with a large number of new and exotic (新奇的) species. In the last few years researchers have discovered the Saola—never-before-seen antelope-like creature, a small deer species called muntjacs, a tiny stripped rabbit and a rock rat that was thought to have been extinct 11 millions years ago. In addition to that it is also home to over one hundred species of large mammals ranging from tigers to macaques and over 165 species of amphibians (两栖动物) and reptiles like the terrible King cobra and the noisy Tokay gecko, a permanent resident inside most Laos households.
64. 1.Which of the following is the best title of passage?
A．Laos full of a large number of exotic species
B．Laos popular with plenty of strange species
C．Every species of insect discovered and recorded by scientists
D．World’s first eyeless spider discovery in Southeast Asia.
65. 2.What does the second paragraph mainly tell us about the unique eyeless spider?
A．The eyesight, identification and family members.
B．The size, identification and the reason for being eyeless
C．The body, species and living environment
D．The size, identification and the species
66. 3.The underlined part “dispensed with” (in 2nd Para) means _________.
A．got rid of B．put up with C．carried away D．taken no notice of
高三英语阅读理解中等难度题查看答案及解析
Scientists think they have answered a mystery: How some ocean creatures got so huge so quickly.
A few million years ago, the largest whales, averaged about 15 feet long. Then seemingly overnight, one type of whale, the toothless baleen whale（须鲸类）became huge. Modern blue whales get as big as 100 feet. Nicholas Pyenson of the Smithsonian Natural History Museum said, “Why is that?” ”It happened in the glance of an evolutionary eye, which makes it harder to figure out what happened,” said Graham Slater, lead author of the study. Their study has suggested an answer: Ice ages in the last 3 to 5 million years started it, changing the oceans and food supply for whales.
The researchers used fossil records of the smaller whales to create a family tree for baleen whales which include blue whales, humpbacks and right whales. Using computer simulations（模拟）and knowledge about how evolution works, they concluded that when the size changes started, the poles got colder, ice expanded and the water circulation in the oceans changed and winds shifted, Slater and Pyenson said cold water went deep and moved closer to the equator(赤道）and then eventually moved back up with small fish and other small animals that whales eat.
Baleen whale, which have no teeth, feed by eating huge amounts of fish they capture. Toothed whales, like sperm whales (抹香鲸), hunt individual fish, so the ocean chants that made food less evenly spread out didn’t affect them as much. But baleen whales hunt schools of fish.
Olivier Lambert at the Royal Belgian Institute of Natural Sciences calls it “a really convincing situation”. But he said the lack of fossils in certain time periods is an issue. As oceans warm from man-made climate change, the seas will be more like it was when the whales smaller and they will have a more difficult time surviving.
1.What does the author mean by “It happened in the glance of an evolutionary eye” in the second paragraph?
A. The change of baleen whales happened too quickly.
B. The change of baleen whales was too difficult to explore.
C. Researchers paid little attention to the change of baleen whales.
D. Researchers thought the change of baleen whales was unimportant.
2.What played the key role in baleen whales’ becoming huge?
A. Man-made climate change.
B. Its eating a huge amount of fish.
C. The water circulation in the oceans.
D. The increase of food supply for whales.
3.What do we know about sperm whales and blue whales according to the text?
A. Sperm whales eat more food.
B. Blue whaler live much longer.
C. Sperm whales prefer to hunt schools of fish.
D. Blue whales usually swallow schools of fish.
4.What can we infer from the last paragraph?
A. There are no whale fossils now.
B. The whales may become even bigger.
C. Global warming has threatened the whales.
D. Olivier Lamber thinks the study is perfect.
高三英语阅读理解中等难度题查看答案及解析
Scientists have been puzzled by the phenomenon that migrating birds fly not just in groups all the time, but in "V" formations and they have tried to figure out what benefit birds get from this particular formation. Now, a research group from University of London may have found the answer ― migrating birds fly in a "V" to save energy, according to a study published in the journal Nature.
When a bird flaps(振翅) its wings, it stirs the air around it and causes it to move indifferent directions. Scientist found in the study that the air creates an upward-moving wave at the tips of the wings, which means that if a bird flies around the wingtips of another bird, it can get a boost（抬高） from the rising air and therefore use less energy to stay in the air.
Apart form the "free ride" strategy, scientists were also surprised to observe that migrating birds timed their wing beats and adjusted their positions in a very precise way to maximize the lifting effect while avoiding areas where the air move downward.
"They're able to sense what's going on from the bird in front, where this 'good air' is coming from and now how to position themselves perfectly in it," lead researcher Steven Portugal told BBC.
In fact, the "V" formation has long thought to help birds fly more efficiently(效率搞地). A previous study showed that birds' heart rates went down when they were flying together in a "V" formation. Jet fighters were also found to be able reduce their energy use by up to 18% by staying near the wingtips of other jet fighters. Both of these findings led scientists to suspect that the "V" formation had an efficiency purpose, but until now they still lack proof.
"For scientists, the new study provides an insight into an interesting natural phenomenon. But it could mean even more for aircraft companies — helping them understand how they can imitate that with their plane formations to save fuel, said Portugal."
1.What is the author's purpose in writing this article?
A. To explain how birds benefit from migration.
B. To introduce how migrating birds find their way.
C. To tell some applications of migrating birds' "V" formations.
D. To report new findings about migrating birds' "V" formations.
2. According to the recent study, when birds migrate .
A. they don't change their lead birds during the whole journey
B. they fly in "V" formations to protect themselves against enemies
C. they form the shape of a "V" to make best use of the lifting effect
D. the air they stir around makes it hard for the birds behind to fly fast
3.What is the significance of the new study according to this article?
A. It might inspire aircraft companies to think of ways to improve efficiency.
B. It has proved that the "V" formation can improve in efficiency in many fields,
C. It has led scientists to discover that birds' heart rates go down when they fly in a "V".
D. It shows that the best formation of jet fighters in battle should be a "V" formation.
4. The underlined word "imitate" in the last paragraph most probably means " ".
A. use B. copy C. change D. learn
高三英语阅读理解中等难度题查看答案及解析
Puzzled by this strange natural phenomenon, the scientists started to explore every _______ they knew to figure it out.
A. impression B. intention C. avenue D. design
高三英语单项填空中等难度题查看答案及解析
Scientists say they now have proof to support the old-fashioned advice that it’s best to sleep on a problem．They say sleep strengthens the memory and helps the brain organize the masses of information we receive each day．
The lead researcher Bob Stickgold at the Harvard Medical School said, “Sleep helps us draw rules from our experiences．It’s like knowing the difference between dogs and cats even if it’s hard to explain．”
The US research team studied how well students remembered connections between words and symbols, reports New Scientist．They compared how the students performed if they had had a sleep between seeing the words and having the test, and if they had not slept．They found that people were better able to remember lists of related words after a night’s sleep than after the same time spent awake during the day．They also found it easier to remember themes that the words had in common．But they forgot around one in four more themes if they had been awake．
Prof．John Groeger, of Survey University’s Sleep Research Centre, said, “People have been trying for years to find out what the purpose of sleep is, as we know that only certain parts of it have a restorative （促使康复的）value．”
“We form and store huge numbers of experiences in the head every day, and sleep seems to be the way the brain deals with them all．”
1.The phrase “to sleep on a problem” in Paragraph 1 most likely means “________”．
A．to pay full attention to a problem
B．to wait until the next day for a decision
C．to sleep to forget a problem
D．to have difficulty in sleeping
2.In the study by the US research team, students were asked to ________．
A．put together words of similar meanings
B．remember words and their meanings
C．show their knowledge of words
D．make up lists of related words
3.Which of the following may be easier to remember?
A．Themes learned right before the test．
B．Rules from personal experiences．
C．Words learned before a good sleep．
D．Ideas stored together in the brain．
4.What may be the importance of the research?
A．It shows that sleep may help us manage information．
B．It helps find out the common themes of words．
C．It tells us that more sleep can improve health．
D．It proves the value of old-fashioned advice．
高三英语阅读理解中等难度题查看答案及解析
I don’t think that your lecture _______ the audience，for they appeared quite puzzled.
A． got across to B． got close to
C． got away with D． got along with
高三英语单项填空中等难度题查看答案及解析
Think hard and you won’t have the puzzle you.
| A．puzzling | B．puzzle | C．to puzzle | D．puzzled |
高三英语单项填空困难题查看答案及解析
How to improve my life? Many people think that they have to accept whatever life throws at them. They'll say, "This is my fate, my destiny. I cannot change it."
Of course not! You don't have to suffer needlessly. Your destiny depends on you, not on any other external factors.
I know someone who says she just accepts what life gives her because she has done everything she can to improve it. Guess what her lifestyle is? She wakes up in the morning, goes to work, comes back home, relaxes, chats with people, watches TV, then goes to sleep. Next day, the same routine cycle follows.
Huh! Is this what she calls "doing her best"? She believes she has tried her best and just accepts it in her heart that this is the life that God has intended for her to live; that her luck can only change if God wills it. Of course God wants us to be happy and live our life to the fullest, but we have to do our share of exerting(运用) the effort to live the life of our dreams.
Remember that you reap what you sow. You just don't sit around and wait for a million dollars to fall from the sky. You have to get off the couch, get your eyes off the TV screen, get your hands off the phone. Don’t expect your luck to change unless you do something about it. If something goes wrong, don't just regard it as a temporary setback; but use it as feedback. Learn your lesson, make the most of the situation, and do something to solve the problem. It's not enough to think positively; you also have to act positively.
If someone's life is in the trouble, do you just hope and pray that things will turn out fine? Of course not! You get to do anything you can to save the person. So it is with your own life. It is not enough to hope for the best, but you have to do your best. In other words, don't just stand (or sit ) there, do something to improve your life.
1.According to the woman mentioned in Para.3, her life ____________.
A. Doesn't need improving B. couldn't be improved
C. will be better some day D. Will be worse in the future
2.What does the author think of the woman's life?
A. positive B. satisfying C. colorful D. passive
3.Which of the following statements is the author's opinion?
A. Your temporary problem is not discouraging.
B. Your luck can be changed by your efforts
C. You can only achieve success when God wills it.
D. You should treat yourself in the way you treat friends.
4.In Para.5, the author emphasized the importance of _____________.
A. positive action B. positive thinking C. hope for the best D. intention to succeed
5.The text is mainly written to advise you to ____________.
A. understand yourself B. improve your life
C. believe in yourself D. change your normal way
高三英语阅读理解中等难度题查看答案及解析
How to improve my life? Many people think that they have to accept whatever life throws at them. They'll say, "This is my fate, my destiny. I cannot change it."
Of course not! You don't have to suffer needlessly. Your destiny depends on you, not on any other external factors.
I know someone who says she just accepts what life gives her because she has done everything she can to improve it. Guess what her lifestyle is? She wakes up in the morning, goes to work, comes back home, relaxes, chats with people, watches TV, then goes to sleep. Next day, the same routine cycle follows.
Huh! Is this what she calls "doing her best"? She believes she has tried her best and just accepts it in her heart that this is the life that God has intended for her to live; that her luck can only change if God wills it. Of course God wants us to be happy and live our life to the fullest, but we have to do our share of exerting(运用) the effort to live the life of our dreams.
Remember that you reap what you sow. You just don't sit around and wait for a million dollars to fall from the sky. You have to get off the couch, get your eyes off the TV screen, get your hands off the phone. Don’t expect your luck to change unless you do something about it. If something goes wrong, don't just regard it as a temporary setback; but use it as feedback. Learn your lesson, make the most of the situation, and do something to solve the problem. It's not enough to think positively; you also have to act positively.
If someone's life is in the trouble, do you just hope and pray that things will turn out fine? Of course not! You get to do anything you can to save the person. So it is with your own life. It is not enough to hope for the best, but you have to do your best. In other words, don't just stand (or sit) there, do something to improve your life.
1.According to the woman mentioned in Para.3, her life ____________.
A．Doesn't need improving B．couldn't be improved
C．will be better some day D．Will be worse in the future
2.What does the author think of the woman's life?
A．positive B．satisfying C．colorful D．passive
3.Which of the following statements is the author's opinion?
A．Your temporary problem is not discouraging.
B．Your luck can be changed by your efforts
C．You can only achieve success when God wills it.
D．You should treat yourself in the way you treat friends.
4.In Para.5, the author emphasized the importance of _____________.
A．positive action B．positive thinking C．hope for the best D．intention to succeed
5.The text is mainly written to advise you to ____________.
A．understand yourself B．improve your life
C．believe in yourself D．change your normal way
高三英语阅读理解中等难度题查看答案及解析