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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
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    A new App has been used in South Africa to benefit (有助于)the relationship between wildlife and humans.

    Roadwatch, created by the Endangered Wildlife Trust (EWT),is designed to let drivers   record any roadkill they see on the country's highways.

    It may seem like a strange idea, but EWT says that it could become the perfect platform for receiving important information. Information on where endangered species (物种)are living and the danger that they are under from traffic can help to inform decisions on conservation of matters (物质守恒)in the future.

    People can use the App through Facebook, WhatsApp, SMS and Linkedin to report the   species, location, time and date of the creature that has been seen on the road.

    Wendy Collinson field officer at EWT suggested that it could lead to more people taking care on the roads and paying more attention to animals that may be trying to cross the roads. One of the biggest problems is with reptiles (爬行动物)and snakes, which she believes people hit on purpose, as they are generally seen as scary. However, they are important to the health of ecosystems, just as all creatures are and also need to be protected.

    Emily Taylor from EWT said, “Roadkill simply hasn't been studied here. The road ecology and how many endangered species are being killed, is something we need to know more about. We want people to report as much as possible.”

    There have been some other Apps to use in relation to wildlife spotting in South Africa, but most of them are about animals that have not been knocked down, including those helping to collect information of where certain species have been seen, such as in parks.

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