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题型:阅读选择 题类:真题 难易度:普通


    It happens every spring. Flowers come out everywhere on the same day. But how do plants “know” when to flower?

For years, it has been a difficult question for scientists. But a US research group may have finally answered it—the secret lies in a protein(蛋白质)called FKF1. This helps plants to know when the days become long and when they get short. Then they can tell the seasons are changing.

    Researchers found the FKF1 protein when they were studying a plant called Arabidopsis(拟南芥). It is sensitive(敏感的)to sunlight, and can be made active by sunlight.

    Plants produce this protein every day in the late afternoon all year. If there is no light at this time, for example in winter when the sun goes down early, the protein won't be active. But when spring comes and the days get longer, the FKF1 protein can be made active by day light and the plants “know”it is time to flower. “If there is light in the late afternoon, plants will know that the days are getting longer and that it is the best time for flowers to come out,”explained Takato Imaizumi, leader of study. But when conditions are poor for growing, such as during autumn or winter when the weather is cold and days are short, plants won't flower.

    Although researchers have only studied how the FKF1 protein works in the Arabidopsis, they believe that it is the same with many other plants, including crops such as rice and wheat. This could be useful to the agricultural industry.

    "If we can control when flowers come out, we might be able to increase crop production,”Imaizumi said.


(1)、The passage is mainly about __________.

A、howplants “know” when to flower  B、what people can do with plants C、how seasons are changing  D、what kind of plant Arabidopsis is
(2)、Scientists found the FKF1 protein when they were __________.

A、answering a question     B、controlling the clours of flowers C、planting flowers in the garden D、studying a plant called Arabidopsis
(3)、The best time for flowers to come out is when __________.

A、it rains in spring  B、there is light in the late afternoon C、it is getting dark         D、the sun goes down early
(4)、 Scientists believe that __________.

A、other plants also know when to flowers B、flowers are more valuable than fruits and vegetables C、people have known how to control when flowers come out D、if the weather is cold and days are short, plants will flower
举一反三
    As we know, it is not easy to build a satellite(卫星). Building a traditional satellite usually takes years. The costs can be as high as $250 million or more. Most members of the design teams have worked in the field for a long time. They hold advanced degrees(学历) in math, science, or engineering.
    But things are changing. High costs, unusual educational needs and long start-up times are no longer an obstacle(障碍) to space exploration. The scientists have developed a new type of tiny, inexpensive earth-orbiting(轨道) satellite.
    So far, college students have built and launched(发射) several cube-shaped satellites, or CubeSats. At least 15 more are ready to go. Those already in orbit take pictures, collect information and send it back to the earth, just as regular satellites do.
    But you might not even have to wait until you get to college to start designing and building your own satellite. A new program called KatySat aims to get teenagers to take part in. When kids understand what satellites can do, the kinds of ideas they'll come up with may be countless.
    Education isn't the only aim of CubeSats because these tiny, technology-filled boxes are  inexpensive to build and can be put together quickly, they're perfect for testing new technologies that might one day be used on major space tasks.
    The biggest challenge now is to find ways to bring the satellites back to the earth after a year or two. Or space junk could gradually increase because CubeSats become more popular.
   Nowadays, college and high school students are getting a chance to learn what it takes to explore in space. Someday—perhaps a lot sooner that you imaging—you might get to design, build and launch your own satellite. If you do, you're sure to have fun. And you might also get crazy about science for life.

阅读理解

    They say music is universal, and it seems to be true since wherever we go, we see people listening, playing or dancing to it. We tend to think that music is larger than our cultural differences and shows the deeper connections between us.

    But according to a recent study published in the Current Biology, music doesn't speak to everyone. There is a condition, the researchers argue, called "musical anhedonia". They say that those who have this condition may have few abilities to experience pleasure from music.

    For the study, 30 people listened to the same, mostly classical music pieces. They were then asked to complete a questionnaire on how they felt about the music. At the same time, the researchers measured their heart rate and skin reaction, which are considered physiological measures of feelings.

    According to the researchers, most of the people in the study got pleasure from the music. They had a quicker heartbeat and sweatedmore. However, a small number of them had very little and even no pleasant feeling while they were listening to the music. These people had none or very few of the physical signs which the others in the study experienced.

    The researchers say that this means people have different abilities to enjoy music and that "there are people who specifically can't enjoy music at all"

    To study the condition more deeply, another group of scientists, at Columbia University, US, researched brain activities. They found that the key is the blood flow to the reward system in the brain. People who got less pleasure from music had comparatively lower blood flow to areas involved in the reward system of the brain when they were listening to music.

    The lower blood flow makes it more likely that the brain's "reward system" will be inactive. And it will produce less of the "pleasure chemical" dopamine. As a result, people get less pleasure from music.

    If the research is correct, according to National Public Radio, there are simply people who just don't get music. They may get pleasure from many things, but a good tune isn't one of them.

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