Against the supposition than forest fires in Alaska, Canada and Siberia warm the climate, scientists have discovered that cooling may occur in areas where burnt trees allow more snow to mirror more sunlight into space.
This finding suggests that taking steps to prevent northern forest to limit the release of greenhouse gases may warm the climate in northern regions. Usually large fires destroyed forests in these areas over the past decade. Scientists predict that with climate warming, fires may occur more frequently over next several centuries as result of a longer fire season. Sunlight taken in by the earth tends to cause warming, while heat mirrored back into space tends to cause cooling.
This is the first study to analyze all aspects of how northern fires influence climate. Earlier studies by other scientists have suggested that fire in northern regions speed up climate warming because greenhouse gases from burning trees and plants are released into the atmosphere and thus trap heat.
Scientists found that right after the fire, large amounts of greenhouse gases entered the atmosphere and caused warming. Ozone(臭氧)levels increased, and ash from the fire fell on faroff sea ice, darkening the surface and causing more radiation from the sun to be taken in. The following spring, however, the land within the area of the fire was brighter than before the fire, because fewer trees covered the ground. Snow on the ground mirrored more sunlight back into space, leading to cooling.
“We need to find out all possible ways to reduce the growth of greenhouse gases in the atmosphere.” Scientists tracked the change in amount of radiation entering and leaving the climate system as a result of the fire, and found a measurement closely related to the global air temperature. Typically, fire in northern regions occurs in the same area every 80 to 150 years. Scientists, however, found that when fire occurs more frequently, more radiation is lost from the earth and cooling results. Specifically, they determined when fire returns 20 years earlier than predicated, 0.5 watts per square meter of area burned are soaked_up by the earth from greenhouse gases, but 0.9 watts per square meter will be sent back into space. The net effect is cooling. Watts are used to measure the rate at which energy is gained or lost from the earth.
【小題1】According to the new findings, taking steps to prevent northern forest fires may ________.
| A．result in a warming climate |
| B．cause the forest fires to occur more frequently |
| C．lead to a longer fire season |
| D．protect the forests and the environment there |
| A．large amounts of greenhouse gases enter the atmosphere |
| B．the levels of ozone which is a type of oxygen increase |
| C．snow on the ground mirrors more sunlight back into space |
| D．a(chǎn)shes from the fire fall on the ice surface and take in more radiation from the sun |
| A．a(chǎn)nalyze all aspects of how northern fires influence climate |
| B．indicate that forest fires will pollute the atmosphere |
| C．suggest that people should take measures to protect environment |
| D．suggest that the fires will speed up climate warming |
| A．released | B．a(chǎn)bsorbed | C．created | D．distributed |
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科目：高中英語 來源： 題型：閱讀理解
One of the most important recent medical breakthroughs has been the impact of gut flora（腸道菌群）on overall health. This dynamic mix of bacteria in the digestive tract（消化道）may affect everything from obesity to asthma（哮喘）．
The Gut-Mood Link
Anyone who's ever experienced "butterflies" in his or her stomach knows that the gut and the brain are connected. But until recently, scientists hadn't realized that the trillions of bacteria in our digestive tract may be driving the relationship.
One recent experiment suggests that you can control calm. Canadian researchers gave healthy mice a mixture of antibiotics, which change the makeup of GI-tract（胃腸道）bacteria. Over two weeks, some animals became more anxious and some less, depending on which drugs they received. In another study, when gut bacteria from calm mice were transferred to anxious mice, the jittery（緊張的）creatures seemed less nervous.
UCLA professor Kirsten Tillisch, doctor of medicine, recently had healthy women eat a yogurt
rich in certain types of "good" probiotic（益生菌的）bacteria. Two 'Control groups ate yogurt without such bacteria or ate nothing. Brain scans of the probiotic-yogurt eaters indicated changes in regions that could be associated with a less-anxious response in fearful or stressful situations compared with the control groups.
Scientists are even exploring whether gut microbes（微生物）might treat some brain disorders. A new study in Cell found that mice with features of autism（自ICJ癥）given a type of bacteria in healthy human GI tracts exhibited less autism-like behavior. In a recent case report, a Boston ps. chiatrist says a course of certain probiotics and antibiotics helped relieve a patient's compulsive disorder. -We tend to focus on how your mood affects your body from the top down, not the bottom up," says Dr. Tillisch. "Now we know that the gut affects how your brain responds to the environment- it's a remarkable change in thinking.”
How Bacteria Talk to the Brain Scientists aren't sure how gut flora affect brain chemistry. One theory is that the bacteria access pathways along the nerve, the main highway in the nervous system that links the brain to the gut. Another is that the bacteria influence the immune system, releasing chemicals that affect conditions like depression. Finally, researchers believe that bacteria produce or affect the metabolism（新陳代瀉'i) of chemicals, which change brain function.
Dr. Tillisch told me that patients always ask which probiotics will lift their mood．Her answer:
"We don't know yet, but we hope to one day." In the future, patients might receive probiotics or transplant（移植） in which bacteria from the gut of a healthy person are transferred to the gut of a sic': one-to prevent or treat mental health issues. But these approaches are years away from primary time．Until then, a diet rich in fruit and veggies helps cultivate（培養(yǎng)）better-balanced microbes than a typical Western diet high in animal and processed products. Avoiding unnecessary antibiotics, particularly in early childhood, may also establish healthier gut bacteria.
【小題1】 According to the passage, gut bacteria might help us in many ways EXCEPT＿_(dá)．
| A．lightening our mood | B．treating autism |
| C．relieving depression | D．transplanting gut flora |
| A．Paragraph 2 | B．Paragraph 3 |
| C．Paragraph 4 | D．Paragraph 5 |
| A．Cultivating a Happier Gut |
| B．Growing Bacteria in the Future |
| C．Balancing Microbes and Diet |
| D．Living a Happy Healthy Life |
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科目：高中英語 來源： 題型：閱讀理解
Global Positioning Systems（GPS） are now a part of everyday driving in many countries. These satellite-based systems provide turn-by-turn directions to help people get to where they want to go. But, they can also cause a lot of problems, send you to the wrong place or leave you completely lost. Many times, the driver is to blame. Sometimes a GPS error is responsible. Most often, says Barry Brown, it is a combination of the two.
We spoke to Mr. Brown by Skype （網(wǎng)絡(luò)電話軟件）. He told us about an incident involving a friend who had flown to an airport in the eastern United States. There he borrowed a GPS-equipped car to use during his stay. BARRY BROWN: “And they just plugged in an address and then set off to their destination. And, then it wasn’t until they were driving for thirty minutes that they realized they actually put in a destination back on the West Coast where they lived. They actually put their home address in. So again, the GPS is kind of 'garbage in garbage out'.”
Mr Brown says this is a common human error. But, he says, what makes the problem worse has to do with some of the shortcomings, or failures, of GPS equipment. BARRY BROWN: “One problem with a lot of the GPS units is that they have a very small screen and they just tell you the next turn. Because they just give you the next turn, sometimes that means that it is not really giving you the overview that you would need to know that it’s going to the wrong place.”
Barry Brown formerly served as a professor with the University of California, San Diego. While there, he worked on a project with Eric Laurier from the University of Edinburgh. The two men studied the effects of GPS devices on driving by placing cameras in people’s cars. They wrote a paper based on their research. It is called “The Normal, Natural Troubles of Driving with GPS.”
It lists several areas where GPS systems can cause confusion for drivers. These include maps that are outdated, incorrect or difficult to understand. They also include timing issues(時機(jī)問題) related to when GPS commands are given.
Barry Brown says, “ To make GPS systems better we need a better understanding of how drivers, passengers and GPS systems work together.”
【小題1】In paragraph 2, Mr. Brown mentioned his friend in the conversation to _______.
| A．build up his own reputation |
| B．laugh at his stupid friend |
| C．prove the GPS system is only garbage |
| D．describe an example of human error |
| A．They just provide the next turn. | B．They are harmful to eyes. |
| C．They make drivers tired easily. | D．They often break down suddenly. |
| A．GPS units are to blame for most GPS service failures. |
| B．We should introduce higher standards for the driving license. |
| C．Cameras are urgently needed to help improve GPS systems. |
| D．Drivers, GPS systems and passengers should unite to improve GPS systems. |
| A．Unconcerned. | B．Prejudiced. |
| C．Objective. | D．Critical. |
| A．Driving with GPS can be difficult. |
| B．Driving confusions can be caused by small screens. |
| C．Driving without GPS should be much more convenient. |
| D．GPS equipment in driving to be deserted or improved |
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科目：高中英語 來源： 題型：閱讀理解
London has become a cycle friendly zone after the launch of a new bike hire scheme. It has been designed to encourage more people to cycle in and around central London.
So how does it work? First you have to sign up to the scheme to be sent a key. The key will unlock one of the bikes, which are kept at docking stations in and around central London. You have to pay an access fee for the key and then you pay as you go, for the length of time you use the bike.
Transport for London, which runs the scheme, is hoping to have 6,000 bikes and 400 docking stations in place by the end of the year. The new hire system is hoping to ease congestion (擁擠 ) in London and is expected to create up t0 40 ,000 extra cycle trips a day into the city centre. London Mayor Boris Johnston launched the scheme and said London had been 6ifilled with thousands of gleaming machines that will transform the look and feel of our streets and become as commonplace on our roads as black cabs and red buses".
However, there have been a few problems since the scheme was launched last Friday. On the first day some people found they couldn't dock their bike properly and their usage of the bike had not registered. Transport for London did admit they had been expecting a few "teething problems" and have said they wouldn't charge for the first day as a "gesture of goodwill". Some other people have criticized the lack of docking stations and locks for the bikes as well as the price it costs to hire the bicycles.
Despite the comments, the green-thinking London Mayor still seems very positive about things, saying, "My campaign for the capital to become the greatest big cycling city in the world has taken a big pedal-powered push forwards. "
【小題1】. London Mayor Boris Johnston launched the new bike scheme in order to______.
| A．reduce the air pollution of the city |
| B．deal with the city's traffic problems |
| C．increase employment opportunities |
| D．encourage the citizens to take exercises |
| A．b→a→c→d | B．b→d→c→a |
| C．d→c→b→a | D．d→b→c→a |
| A．the high cost to hire a bike |
| B．docking the bikes properly |
| C．not registering their usage of the bikes |
| D．not charging for the first day of the scheme |
| A．the cycling revolution is not successful |
| B．a(chǎn)ll the citizens in London support the scheme |
| C．the London Mayor is confident in the scheme |
| D．the scheme will be cancelled because of the problems |
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科目：高中英語 來源： 題型：閱讀理解
Would it surprise you to learn that, like animals, trees communicate with each other and pass on their wealth to the next generation?
UBC Professor Simard explains how trees are much more complex than most of us ever imagined. Although Charles Darwin thought that trees are competing for survival of the fittest, Simard shows just how wrong he was. In fact, the opposite is true: trees survive through their co-operation and support, passing around necessary nutrition "depending on who needs it".
Nitrogen (氮) and carbon are shared through miles of underground fungi (真菌)
networks, making sure that all trees in the forest ecological system give and receive just the right amount to keep them all healthy. This hidden system works in a very similar way to the networks of neurons (神經(jīng)元) in our brains, and when one tree is destroyed, it affects all.
Simard talks about "mother trees", usually the largest and oldest plants on which all other trees depend. She explains how dying trees pass on the wealth to the next generation, transporting important minerals to young trees so they may continue to grow. When humans cut down "mother trees" with no awareness of these highly complex "tree societies" or the networks on which they feed, we are reducing the chances of survival for the entire forest.
"We didn't take any notice of it" Simard says sadly. "Dying trees move nutrition into the young trees before dying, but we never give them chance." If we could put across the message to the forestry industry, we could make a huge difference towards our environmental protection efforts for the future.
【小題1】The underlined sentence "the opposite is true" in Paragraph 2 probably means that trees .
| A．compete for survival |
| B．protect their own wealth |
| C．depend on each other |
| D．provide support for dying trees |
| A．look the largest in size in the forest |
| B．pass on nutrition to young trees |
| C．seem more likely to be cut down by humans |
| D．know more about the complex "tree societies" |
| A．how "tree societies" work |
| B．how trees grow old |
| C．how forestry industry develops |
| D．how young trees survive |
| A．Old Trees Communicate Like Humans |
| B．Young Trees Are In Need Of Protection |
| C．Trees Are More Awesome Than You Think |
| D．Trees Contribute To Our Society |
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科目：高中英語 來源： 題型：閱讀理解
(2014·德州模擬)Some animals will defend their territory by fighting with those who try to invade it.Fighting，however，is not often the best choice，since it uses up a large amount of energy，and can result in injury or even death.Most animals rely on various threats，either through sounds or smells.The songs of birds，the drumming of woodpeckers and the loud calls of monkeys are all warnings that carry for long distances，advertising to possible invaders that someone else’s territory is being approached.Many animals rely on smells to mark their territories or leaving droppings around the territories.Other animals will be warned off the territory without ever meeting with the territory’s defender. 
Sometimes，these warnings may be ignored，and an invader may move accidentally into a neighboring territory，or two animals may meet near the border of their nearby territories.When the two animals meet，they will generally threaten each other with visual (視覺的) displays.These displays will often exaggerate an animal’s size by putting up feathers or fur，or will show off the animal’s weapons.The animals may go through all the behavior of fighting without ever actually touching each other.The displays are generally performed best near the center of an animal’s territory，where it is more likely to attack an invader and where retreating becomes more of a choice.
Actual fighting usually only happens in overcrowded conditions，when resources are not enough.Serious injury can result，and old or sick animals may die，leading to a more balanced population size.Under most natural conditions，territoriality is an effective way of maintaining a healthy population.The study of social behaviors such as territoriality in animals may also help us to understand human society.
【小題1】What topic is the passage mainly involved in?
| A．What animals’ territory is usually like. |
| B．How animals deal with different threats. |
| C．How animals defend their territory. |
| D．Where animal fights take place frequently. |
| A．Fighting in groups. |
| B．Threatening and warning. |
| C．Escaping before being hurt. |
| D．Asking partners for help. |
| A．enlarge | B．change |
| C．shake | D．shrink |
| A．a(chǎn)nimals meet near the border of their territories |
| B．the invader enters the defender’s territories |
| C．the defender notices the invader smaller than itself |
| D．the living resources are limited in the territory |
| A．communication | B．condition |
| C．population | D．migration |
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科目：高中英語 來源： 題型：閱讀理解
Nuclear power's danger to health, safety, and even life itself can be summed up in one word: radiation.
Nuclear radiation has a certain mystery about it, partly because it cannot be detected by human senses. It can't be seen or heard, or touched or tasted, even though it may be all around us. There are other things like that. For example, radio waves are all around us but we can't detect them, sense them, without a radio receiver. Similarly, we can't sense radioactivity without a radiation detector. But unlike common radio waves, nuclear radiation is not harmless to human beings and other living things.
At very high levels, radiation can kill an animal or human being immediately by killing masses of cells in vital organs. But even the lowest levels can do serious damage. There is no levels of radiation that is completely safe. If the radiation does not hit anything important, the damage may not be serious. This is the case when only a few cells are hit, and if they are killed immediately. Your body will replace the dead cells with healthy ones. But if the few cells are only damaged, and if they reproduce themselves, you may be in trouble. They can grow into cancer. Sometimes this does not show up for many years.
This is another reason for some of the mystery about nuclear radiation. Serious damage can be done without the victim being aware at the time that damage has occurred. A person can be irradiated(輻射)and feel fine, then die for cancer five, ten, or twenty years later as a result. Or a child can be born weak as a result of radiation absorbed by its grandparents.
Radiation can hurt us. We must know the truth.
【小題1】Which of the following statements is true?
| A．Nuclear radiation is just like common radio waves. |
| B．Nuclear radiation can cause cancer to human beings. |
| C．Nuclear radiation can be detected by human senses. |
| D．Nuclear radiation can be safe to human beings if its level is low. |
| A．By damaging its heart. |
| B．By killing a few cells. |
| C．By hitting any place in its body. |
| D．By killing many cells in important organs. |
| A．die of cancer after many years |
| B．die immediately |
| C．have a child who may be born weak |
| D．a(chǎn)ll of the above |
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科目：高中英語 來源： 題型：閱讀理解
DNA left at a crime scene could be used in the future to build up a picture of an offender’s face, it was revealed tonight.
A first step towards genetic mugshots has been taken by researchers in the US who link specific DNA markers with face shape. To identify the genes, they focused on known mutations(突變) that cause changes of the face and head. Normal versions of these genes were found to influence individual features. For instance, one gene affected the lips, another the shape and configuration of bones around the eyes, and a third the appearance of the mid-face and skull. In total, 20 genes had “significant effects” on facial appearance.
Lead scientist Professor Mark Shriver, from Pennsylvania State University, said: “We use DNA to match to an individual or identify an individual, but you can get so much more from DNA. Currently we can’t go from DNA to a face, or from a face to DNA, but it should be possible.” The implications are far reaching, raising the possibility of creating a data bank of facial types based on genetic markers. DNA from a crime scene could then be used to produce a rough image of the face of an offender or victim. Such genetic mugshots may be more reliable than computer-generated “e-fits” based on witnesses’ recollections. Other uses of the technique might include proving the identity of fathers in paternity cases, or visualising our remote ancestors from fossil DNA.
The scientists wrote in the online journal Public Library of Science Genetics: “Such predictive modelling could be forensically useful; for example, DNA left at crime scenes could be tested and faces predicted in order to help to narrow the pool of potential suspects. Further, our methods could be used to predict the facial features of descendants, deceased ancestors, and even extinct human species. In addition, these methods could prove to be useful diagnostic tools.” The team developed a model which first established a range of physical face shapes from people of mixed West African and European ancestry from the US, Brazil and Cape Verde. Measurements were taken of thousands of point co-ordinates on grids placed over 3D images of the faces.
Statistical methods were then used to determine the relationship between facial differences and the effects of gender, ethnic ancestry and individual gene variants.
【小題1】The underlined word “mugshots” in the second paragraph most probably means _________.
| A．different faces | B．characteristics | C．pictures of faces | D．genders |
| A．they can merely match to an individual or identify an individual |
| B．there is a possibility of going from DNA to a face |
| C．DNA could be used to produce a rough image of an offender’s face |
| D．this technology is more reliable than computer-generated “e-fits” |
| A．Creating a data bank of DNA |
| B．Recognizing the DNA of criminals |
| C．Predicting the location of offence using DNA |
| D．Building image of offender’s face from DNA |
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科目：高中英語 來源： 題型：閱讀理解
If English means endless new words, difficult grammar and sometimes strange pronunciation, you are wrong. Haven’t you noticed that you have become smarter since you started to learn a language?
According to a new study by a British university, learning a second language can lead to an increase in your brain power. Researchers found that learning other languages changes grey matter. This is the area of the brain which processes information. It is similar to the way that exercise builds muscles.?
The study also found the younger people learn a second language, the greater the effect is.
A team led by Dr Andrea Mechelli, from University College London, took a group of Britons who only spoke English. They were compared with a group of “early bilinguals” who had learnt a second language before the age of five, as well as a number of later learners.
Scans showed that grey matter density(密度)in the brain was greater in bilinguals than in people without a second language. But the longer a person waited before mastering a new language, the smaller the difference.?
“Our findings suggest that the structure of the brain is changed by the experience of learning a second language,” said the scientists.?
It means that the change itself increases the ability to learn.?
Professor Dylan Vaughan Jones of the University of Wales, has researched the link between bilingualism and maths skills. “Having two languages gives you two windows on the world and makes the brain more flexible(靈活的),”he said. “You are actually going beyond language and have a better understanding of different ideas.”
The findings were matched in a study of native Italian speakers who had learned English as a second language between the ages of two and 34. Reading, writing, and comprehension were all tested. The results showed that the younger they started to learn, the better. “Studying a language means you get an entrance to another world,” explained the scientists.
【小題1】The main subject talked about in this passage is ______.
| A．science on learning a second language |
| B．language can help brain power |
| C．man's ability of learning a second language |
| D．language learning and maths study |
| A．make people believe language learning helps grey matter work well |
| B．prove that one needs more practice when he (she) is learning a language |
| C．to show the importance of using the language when you learn the language |
| D．say language is also a kind of physical labor |
| A．a(chǎn) researcher on language learning |
| B．a(chǎn)n English native speaker |
| C．a(chǎn)n active language learner |
| D．a(chǎn) person who can speak two languages |
| A．the ability of learning a second language is changing all the time |
| B．there is no difference between a later second language learner and one who doesn't know a second language |
| C．the experience of learning a second language has bad effect on people's brain |
| D．the earlier you start to learn a second language, the higher the grey matter density is |
| A．early learning of a second language helps you a great deal in studying other subjects |
| B．learning a second language is the same as studying maths |
| C．Italian is the best choice for you as a second language |
| D．you’d better choose the ages between 2 and 34 to learn a second language |
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