Question

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 cast sides of their stems grew more rapidly than the west sides. Ai 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, called auxin, appears to be a key driver.

The “dance” to the sun cycle obviously slows when the sunflower matures 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 “slaking” probably mean in Paragraph 3?

A. Tracking.    B. Fastening.

C. Preserving.    D. Researching.

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

A. They won’t grow well.

B. They will grow faster than usual.

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

D. They will produce a number of new genes.

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.

Answer

were not as tough and leafy as those, A选项They won’t grow well.

【解析】每天向日葵会随着太阳的方向而转动摇摆，加州大学的教授Harmer做了一系列研究发现向日葵向阳会使它更好地生长，吸引更多的昆虫授粉。

1.C推理判断题。根据文章前两段得知加州大学的Harmer对向日葵做了一系列实验研究为什么向日葵会追随太阳的方向而变换方向。故选C。

2.B词义猜测题。根据文章so that they could not move,它不能动和 sunflowers prevented from moving. 阻止向日葵移动。得知划线词是“系紧”。A. Tracking.跟踪； B. Fastening.系紧；C. Preserving.保留； D. Researching.研究。故选B。

3.A 细节理解题。根据文章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.Harmer教授发现系紧向日葵后它们长得柔弱、叶子少。故选A。

4.A 细节理解题。根据文章最后一段“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.” 向日葵的向阳性使它变得温暖这样对昆虫很有吸引力。故选A。

【名师点睛】

文章细节的理解可以细化为：（1）一一对应型。答案与题目在表达形式和意义上直接吻合，一一对应，一目了然。属于浅层次的阅读试题，分数比例较少。（2）语言转述型。这是一类间接事实细节题，答案与题目在意义上从分运用了词义之间的转述关系，即正确选项是原文有关词语和句子的另类表达。属于中档难度题，分数比例较大。（3）语意理解型。这是一类深层事实细节理解题，答案与题目之间存在着一定的逻辑联系，这种联系需要建立在事实的基础上通过上、下文来进行判断、分析、归纳和整合，才能得出正确答案。属于较高难度的事实细节题。（4）是非辨别型。这是一类综合事实细节题，出题形式常常是“三正一误”(三项正确，只有一项不符合原文内容)或“三误一正”（三项错误，只有一项符合原文内容)。（5）事实排序型。这是一类运用多项事实进行排序的事实细节题，要求根据动作发生的先后顺序、时间顺序或者句子之间的逻辑关系，找出时间发生，发展的正确顺序。例如：本文的第4小题：

3.A【解题剖析】此题属于细节理解中的（1）一一对应型。答案与题目在表达形式和意义上直接吻合。

【答案定位】根据文章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.Harmer教授发现系紧向日葵后它们长得柔弱、叶子少。故选A。

【推理关系】题干What is the result of sunflowers being stopped from moving?.☞文章内容were not as tough and leafy as those