题目内容

It is easy for us to tell who our family members are, but do plants recognize(识别) their own family? Some do, scientists say, according to a report by Science News in early 2010.
Guillermo P. Murphy and Susan Dudley are two plant scientists from McMaster University in Hamilton, Canada. They did a few experiments with Jewelweeds, a kind of flower that grows in wet, shady spots. They found that the flowers seem to know their own flower family. In their experiments, Murphy and Dudley planted jewelweeds in pots with either siblings or strangers.
When jewelweeds were planted in pots with strangers, the plants started to grow more leaves than if they had been planted alone. This response(反应)suggests that plants are competing with strangers for sunlight, since a plant with more leaves can receive more light and make more food. Jewelweeds usually grow in the shade, where sunlight is not enough.
When jewelweed seedlings(幼苗)were planted with siblings, they grew a few more branches than they usually would if they were alone – but they did not start growing lots of extra leaves. This behavior suggests the plants are more likely to share resources, rather than compete.
According to the Science News report, Jewelweeds are not the first plants that plant scientists have studied for family recognition. In 2007, Dudley and her team studied the Great Lakes sea rocket, a plant that grows on the beach – where it may be hard to get fresh water. In that experiment, the scientists found that when sea rockets were planted with siblings, they tolerated each other. But when they were planted with strangers, the sea rockets reacted by working extra hard to grow lots of roots.
Dudley says this just because sea rockets, on the beach, get plenty of sun but struggle for water – so when they’re threatened, they compete for water. Jewelweeds have plenty of water but have to compete for sunshine, so they grow more leaves.
【小题1】 What does the underlined word siblings mean?

A.Flowers come from foreign countries.
B.Plants growing in different environments.
C.Flowers planted with lots of strangers.
D.Plants that are the same kind.
【小题2】 In the text, the writer mentioned the experiments of Jewelweeds to         .
A.make a comparisonB.introduce a topic
C.describe a pretty flowerD.build a new theory
【小题3】 According to the passage, flowers planted alone will         .
A.grow more leaves than those planted in groups
B.become taller than those with more branches
C.grow fewer leaves than those planted with strangers
D.become ill easily because they can’t get enough shade
【小题4】 What can be the best title for the passage?
A.New Discoveries about Plants
B.How Plants Compete with Each Other
C.Family Recognition among Plants
D.Jewelweeds and the Great Lakes Sea Rockets


【小题1】D
【小题2】B
【小题3】C
【小题4】C

解析试题分析:这篇文章讲的是科学家通过做实验,发现将一种植物与不同种类的植物种植在一起,它会和其他植物竞争养分,将会长的更好,如果单独种植的话,则会分享资源,而不竞争。
【小题1】推断题。由第二段最后一句In their experiments, Murphy and Dudley planted jewelweeds in pots with either siblings or strangers.在他们的实验中,Murphy and Dudley将凤仙花要么和同类植物种植在一起,要么和不同的植物种植在一起。由后面的词义可推出siblings的意思是同类植物。故选D
【小题2】推断题。从第一自然段Some do, scientists say, according to a report by Science News in early 2010.可知植物也能够分辨出它的同类,第二自然段对这个说法进行了一项有关jewelweeds凤仙花的研究,所以在此是为了点明主题。
【小题3】细节题。由第三段第一句When jewelweeds were planted in pots with strangers, the plants started to grow more leaves than if they had been planted alone.当把凤仙花和不同种类的植物种植在一起时,它就会比单独种植时生长出更多的叶子。故可知,答案选C
【小题4】主旨题。这篇文章讲的是科学家通过实验,发现植物也可以辨别出哪些植物与自己是同一种类的。故选C.
考点:科普类说明文
点评:本文较难,科技类的文体是比较繁琐的,因为专有名词较多。学生在解答这类题目时,首先对文章有大致的掌握,对于文章一遍没有看懂时,可以先看题目,按照文章题目的提示,再在文章中找出相对应的地方,然后仔细分析文章的上下文,同时对于专有名词可以用笔画出,通过多个地方的比较就可以猜出意思了。

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We are all busy talking about using the Internet, but how many of us know the history of the Internet?
Many people are ___36___ when they find that the Internet was set up in the 1960s. At that time, computers ___37___ large and expensive. Computer networks didn’t work well. If one computer in the network ___38___ down, the whole network stopped. ___39___ a new network system(系统)had to be set up. It should be ___40___ to be used by many different computers. If part of the network was not working, ___41___ could be sent through another part. In this way computer network system would keep on ___42___ all the time.
At first the Internet was only used by the government, but in the early 1970s, universities, hospitals and banks were allowed to use it too. However, computers were still very expensive and the Internet was difficult to use. By the start of the 1990s, computers became cheaper and ___43___ to use. Scientists had also developed software that made “surfing”(浏览)the Internet more convenient.
Today it is easy to get on-line and it is said that millions of people use the Internet every day. ___44___ e-mail is more and more popular among students. The Internet has now become one of ___45___ parts of people’s life.

【小题1】
A.surpriseB.surprisingC.surprisedD.surprises
【小题2】
A.isB.areC.wasD.were
【小题3】
A.breakB.breaksC.brokeD.would break
【小题4】
A.BecauseB.SoC.ButD.However
【小题5】
A.good enoughB.well enoughC.enough goodD.enough well
【小题6】
A.informationB.informationsC.an informationD.the informations
【小题7】
A.workB.to workC.workingD.worked
【小题8】
A.easyB.easilyC.more easilyD.easier
【小题9】
A.SendB.SendingC.To be sentD.Sent
【小题10】
A.importantB.more importantC.most importantD.the most important

The expression “down to earth” means being open and honest. It is easy to get on with some one who is down to earth. A down-to-earth person is the opposite of someone who acts important or proud.
Down-to-earth people could be important members of society. But they do not consider themselves to be better than others who are less important. A person who is filled with his own importance and pride is said to“ have his nose in the air”.
Americans use another expression that is similar in some ways to down to earth. The expression is“ both feet on the ground”. Someone with both feet on the ground is a person with a good understanding of reality. He may have dreams, but he does not allow them to have influence on his understanding of what is real.
The opposite kind of person is one who “has his head in the clouds”. Someone with his head in the clouds is a person whose mind is not on what is happening in real life. Such a person may be called a day-dreamer.
When we have both our feet on the ground, and when we are down to earth, we do not have our noses in the air. We act honestly and openly to others. Our lives are like the ground below us---solid and strong.
【小题1】A down-to-earth person could be _____.

A.social and proudB.good and opposite
C.real and important D.strong and changeable
【小题2】The expression “has one’s nose in the air” means ______.
A.扬眉吐气B.目中无人C.瞻前顾后D.装模作样
【小题3】If you only consider your own importance, _____.
A.you’ll think you are better than others
B.your life will be like the solid and strong ground
C.you’ll be hated by down-to-earth people
D.your life will be filled with love.
【小题4】If you want to understand what is real in life, you have to ____.
A.get along with other people easily
B.learn from those who are down to earth
C.be a good dreamer with quick mind
D.have your head in the clouds.
【小题5】This passage mainly talks about ______.
A.the use of some expressions
B.dreams and achievements
C.the lifestyle of honest people
D.honest and understanding

Now I know that we black people are much more likely to have high blood pressure and diabetes (糖尿病) than white people. And they often lead to heart attacks and other untreated diseases. For example, black people are three to four times more likely than white people to have high blood pressure and twice as likely as the white population to die of a stroke (中风).
New research has found out the surprisingly high levels of salt in many of black people’s favorite meals. I stopped putting extra salt in my food at the table long ago and I try to cut down on the salt. I use in cooking. The suggested daily level of salt for adults is 6 grams. It is easy to see that if you try not to eat too many processed (加工过的) foods and use salt in your cooking within the limit, you won’t reach more than the daily level.
The research showed how much salt there is in some foods that we buy from restaurants and takeaways. An average salad with rice and peas has 6.2 grams of salt. This is more salt than you are supposed to eat for the whole day.
A researcher talked about the importance of home cooking rather than take-outs. At home, he pointed out, not only can you hold control of the salt bottle, but also you can create tasty food which is low on salt. The researcher later provided curry goat and rice and peas. They were low on salt, but completely delicious.
I do not suppose Jamaicans are going to stop buying takeaways soon. But if you suffer from high blood pressure, it is probably better not to buy them often.
【小题1】The underlined word “they” in Paragraph 1 refers to _______.

A.white peopleB.black people
C.untreated diseasesD.high blood pressure and diabetes
【小题2】What has the new research found out according to Paragraph 2?
A.Black people take in too much salt.
B.Black people’s meals are very special.
C.Processed foods have too much salt in them.
D.6 grams of salt per day is enough for an adult.
【小题3】What would the writer probably suggest black people do?
A.Order no salad in a restaurant.B.Take in no salt for several days.
C.Stop cooking their favorite meals.D.Eat less takeaways.
【小题4】The researcher provided curry goat and rice and peas in order to _______.
A.thank those who came to his home for his research
B.let people know that eating less salt makes one healthier
C.show that tasty food with less salt can be made at home
D.prove the less salt the food has the more delicious it is
【小题5】What would be the best title for this passage?
A.Watch the saltB.Take care, black people
C.Say no to takeawaysD.Say no to high blood pressure

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