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Young sunflowers turn and swing every da...

    Young sunflowers turn and swing every day. New findings add to evidence that the plants are animal-like.

Harmer, a professor in the University of California at Davis, Department of Plant Biology, carried out a series of experiments on sunflowers in the field, in pots outdoors and in indoor growth chambers.

By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun. He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move. When plants were moved indoor with a settled overhead light, they continued to swing back and forth for a few days.

The indoor plants did start tracking the “sun” again when the apparent source of lighting was moved across the room. The plants could reliably track the movement and return at night when the artificial day was close to a 24-hour cycle, but not when it was closer to 30 hours.

When sunflowers track the sun, the east sides of their stems grew more rapidly than the west sides. At night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day or on the other side at night. A plant growth-regulating hormone (激素), called auxin, appears to be a key driver.

The “dance” to the sun cycle obviously slows when the sunflower matures (成熟) and its flowers open up. At that point, the plants stop moving during the day and settle down facing the sun in the east.

“Bees like warm flowers.” Harmer said, adding that the bees are cold-blooded, so landing on a warm flower saves them energy and perhaps feels really good.

“The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.” he said “We’re currently testing this idea.”

1.Why did Harmer do the experiment on sunflowers?

A.To see how sunflowers grow up.

B.To show what sunflowers’ genes are.

C.To study why sunflowers track the sun.

D.To check if sunflowers swing in cloudy days.

2.What does the underlined word “staking” probably mean in Paragraph 3?

A.Tracking. B.Fining.

C.Growing. D.Searching.

3.What is the result of sunflowers being stopped from moving?

A.They will produce a number of new genes.

B.They will grow faster than usual.

C.They won’t swing back though set free.

D.They won’t grow well.

4.What is the advantage of sunflowers’ dance to the sun?

A.They attract more insects. B.They save more energy.

C.They mature more rapidly. D.They produce more flowers.

 

1.C 2.B 3.D 4.A 【解析】 本文是一篇说明文。年轻的向日葵每天都在旋转和摇摆。新的发现进一步证明这些植物与动物相似。本文介绍向日葵随着太阳转动的原因。 1.推理判断题。根据第五段When sunflowers track the sun, the east sides of their stems grew more rapidly than the west sides. At night, the west sides grew faster as the stem swung the other way. The team identified a number of genes that were expressed at higher levels on the sunward side of the plant during the day or on the other side at night. A plant growth-regulating hormone (激素), called auxin, appears to be a key driver.(当向日葵沿着太阳生长时,其茎的东侧比西侧生长得更快。到了晚上,随着茎杆向另一边摆动,西边长得更快了。研究小组发现了一些基因,这些基因白天在植物向阳的一侧表达水平较高,而晚上则在植物的另一侧表达水平较高。植物生长调节激素,生长素,似乎是一个关键的驱动因素)可知,Harmer用向日葵做实验的目的是研究向日葵为什么会追踪太阳。故选C。 2.词句猜测题。根据第三段第一句By staking plants so that they could not move, Harmer showed that he could destroy their ability to track the sun.(通过staking植物,目的是它们不能移动,Harmer认为他可以摧毁他们的太阳跟踪的能力)可推知,Harmer把植物固定住了,由此可知,划线词意为“固定,捆绑”。故选B。 3.推理判断题。根据第三段第二句He also noticed that sunflowers prevented from moving were not as tough and leafy as those that were free to move.(他还注意到,被阻止移动的向日葵不像那些可以自由移动的向日葵那样坚硬和多叶)可知,向日葵被阻止移动后不能很好地生长。故选D。 4.细节理解题。根据最后一段中的The morning warmth changes the flowers in a way to make them more appealing to insects, perhaps causing them to release more attractive scents earlier in the day.(早晨的温暖在某种程度上改变了花朵,使它们对昆虫更有吸引力,可能导致它们在一天的早些时候释放出更有吸引力的气味)可知,向日葵迎着太阳跳舞的好处是它们能吸引更多的昆虫。故选A。
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    Every man wants his son to be somewhat of a clone, not in features but in footsteps. As he grows you also age, and your ambitions become more unachievable. You begin to realize that your boy, in your footsteps, could probably accomplish what you hoped for. But footsteps can be muddied and they can go off in different directions.

My son Jody has hated school since day one in kindergarten. Science projects waited until the last moment. Book reports weren’t written until the final threat.

I’ve been a newspaperman all my adult life. My daughter is a university graduate working towards her master’s degree in English. But Jody? When he entered the tenth grade he became a “vo-tech” student (技校学生). They’re called “motorheads” by the rest of the student body.

When a secretary in my office first called him “motorhead”, I was shocked. “Hey, he’s a good kid, ” I wanted to say. “And smart, really.”

I learned later that motorheads are, indeed, different. They usually have dirty hands and wear dirty work clothes. And they don’t often make school honor rolls (光荣榜).

But being the parent of a motorhead is itself an experience in education. We who labor in clean shirts in offices don’t have the abilities that motorheads have. I began to learn this when I had my car crashed. The cost to repair it was estimated at $800. “Hey, I can fix it,” said Jody. I doubted it, but let him go ahead, for I had nothing to lose.

My son, with other motorheads, fixed the car. They got parts from a junkyard, and ability from vo-tech classes. The cost was $25 instead of $800.

Since that first repair job, a broken air-conditioner, a non-functioning washer and a non-toasting toaster have been fixed. Neighbours and co-workers trust their car repairs to him.

These kids are happiest when doing repairs. They joke and laugh and are living in their own relaxed world. And their minds are bright despite their dirty hands and clothes.

I have learned a lot from my motorhead: publishers need printers, engineers need mechanics, and architects need builders. Most important, I have learned that fathers don’t need clones in footsteps or anywhere else.

My son may never make the school honor roll. But he made mine.

1.What used to be the author’s hope for his son?

A.To avoid becoming his clone. B.To resemble him in appearance.

C.To develop in a different direction. D.To reach the author’s unachieved goals.

2.What can we learn about the author’s children?

A.His daughter docs better in school.

B.His daughter has got a master’s degree.

C.His son tried hard to finish homework.

D.His son couldn’t write his book reports.

3.The author let his son repair the car because he believed that       .

A.his son had the ability to fix it B.it would save him much time

C.it wouldn’t cause him any more loss D.other motorheads would come to help

4.What did the author realize in the end?

A.It is unwise to expect your child to follow your path.

B.It is important for one to make the honor roll.

C.Architects play a more important role than builders.

D.Motorheads have greater ability than office workers.

 

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Facebook

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SparkNotes

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Wikipedia

While Wikipedia isn’t aimed specifically at students, it is difficult to think of another website that does more to reduce the pain of paper writing and researching. Wikipedia gives you a quick way to find sources and get the details of almost any topic you need to research — all without walking to the library.

1.The passage was mainly written to ________.

A. explain some websites for parents

B. compare some educational websites

C. offer some websites that may help students

D. introduce different parts of a website

2.While you are taking great pains to write a research report, ________ can most probably be a help.

A. Facebook    B. Wikipedia    C. Amazon.com    D. SparkNotes

3.RateMyPorfessors.com is a place ________.

A. where you can make friends all over the country

B. that gives you information about professors in advance

C. where you can communicate with your professors

D. that gives tips on how to get along with your professors

4.Which of the following will you most probably refer to, if you need brief ideas for class discussion in reading?

A. Wikipedia.    B. Facebook.    C. SparkNotes.    D. Amazon.com.

 

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    My son Tom taught me a beautiful lesson today. He is three years old and it is amazing hatching him grow up.

He called out to me today saying, “Papa, sit”. That usually means _______ everything and going next to him and sitting down to play with him. I did that, as he can be _______ and will not stop calling out until I _______. He was playing with beads (珠子), pushing a string through them, which is a great exercise to help _______ fine motor skills. Then, after he finished playing with the beads, it was time to put them back in the box that they are stored in. I saw him _______ pick up each bead, look at it _______ it were made of chocolate and then placed it into its box.

With over a hundred beads to go, I was getting _______. “What a long time it will take! Why cannot he _______ ten beads in one go and drop them in?” said my anxious mind. I noticed that he did this with as much_______ as he had while we were playing. I didn’t see any ________ between his play and his putting away the toy. Obviously he enjoyed both.

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Looking at how ________ my son was putting beads into the box ________ me that the process was the goal. The joy of pilgrimage (朝圣) is not in getting there but in every ________ of the journey.

This is what living in the NOW is all ________. Tom, my son, was showing me that it was about thoroughly enjoying every moment with ________ love and peace.

1.A.wasting B.leaving C.taking D.preparing

2.A.stubborn B.innocent C.helpful D.humorous

3.A.fell down B.turned round C.burst out D.gave in

4.A.highlight B.develop C.illustrate D.identify

5.A.gratefully B.eagerly C.carefully D.quickly

6.A.as if B.even though C.in case D.in that

7.A.fascinated B.satisfied C.impatient D.energetic

8.A.package B.grab C.deliver D.replace

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10.A.sense B.difference C.need D.value

11.A.excited B.helped C.struck D.encouraged

12.A.process B.morning C.experiment D.design

13.A.victory B.challenge C.difficulty D.pleasure

14.A.urgent B.decisive C.perfect D.dangerous

15.A.matters B.happens C.disappears D.works

16.A.successfully B.peacefully C.responsibly D.systematically

17.A.guaranteed B.warned C.promised D.taught

18.A.plan B.destination C.step D.detail

19.A.for B.with C.about D.from

20.A.complete B.available C.additional D.precious

 

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