down 1)副词.“向下.下去 .位于动词后.如:sit down 坐下 2)介词.“沿着 .如:Go down this street. 沿着这条街走.——青夏教育精英家教网—

down 1)副词.“向下.下去 .位于动词后.如:sit down 坐下 2)介词.“沿着 .如:Go down this street. 沿着这条街走. 【查看更多】

（10分）植物具有向重力生长的特性，下列是研究根向重力生长机理的两个实验。
实验一：将空白琼脂和含EDTA的琼脂做成帽状，分别套在甲、乙两组玉米胚根的根冠外（示意图如下）。提示：EDTA的作用是去除与其临接部位的 Ca²⁺。

将胚根水平放置培养一定时间后，观察到甲组胚根向重力（下）生长，乙组胚根水平生长。根据上述实验结果，得出实验结论：                               。
　　实验二：水平放置的胚根弯曲向下生长，与根冠近地侧的Ca²⁺浓度明显高于远地侧有关。研究表明，根总是朝着Ca²⁺浓度高的方向弯曲生长。为验证这一结论，有人设计了下列实验方案。请根据提供的实验材料和用具，写出第二步及以后的实验步骤和实验结果，并回答问题。
（1）实验材料和用具：胚根等长的萌发玉米种子，空白琼脂帽，含EDTA的琼脂帽，上面部分含Ca²⁺的琼脂帽（水平方向），培养皿等。
（2）实验步骤：
　　第一步：取若干个培养皿，在每个培养皿中放置适量的萌发玉米种子，按实验一中乙组的方法处理胚根一定时间后，移去根冠外的琼脂帽。然后将培养皿平均分成两组，编号为 A组、B 组。
　　第二步：                                                            。
　　第三步：                                                            。
（3）实验结果：                                                         。
（4）科学家进一步证实，根冠中生长素的分布受Ca²⁺浓度影响，当胚根水平放置时，重力诱导Ca²⁺向根冠下侧移动，导致近地侧的生长素浓度比远地侧高。请分析胚根的生长素分布与向重力生长的关系：                                  。

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阅读理解。

          New rules and behavior standards (行为规范) for middle school students came out in March. The Middle
School is going to use a new way to decide who the top students are. The best students won't only have high
marks. They should not dye (染) their hair, smoke or drink because they are students. The following are some
of the new rules.
         Have you ever copied someone else's work in an exam? Don't do that again! That's not something an
honest student should do.
         Do more at school. Good students love animals and care for other people. April is Bird-loving Month in
China. Is your school doing anything to celebrate it? You should join! And you can learn more about animals
and how to protect them. Be friendly to the people around you. Try to think of others, not only yourself.
          Be open to new ideas. Do you think people can live on the moon? Maybe you'll find another earth
someday. Don't look down on new ideas. Everyone's ideas are important. You should welcome them, because
new ideas make life better for everyone.
          Protect yourself. Has someone ever taken money from one of your classmates? Don't let it happen to
you. If you have to go home late, you should let your parents know.
          Use the Internet carefully. The Internet can be very useful for students. But some things on the Internet
aren't for children, so try to look at web pages (网页) that are good for you.

1. What's the meaning of "look down on " in the passage?

[ ]

A. 向下看
B. 轻视
C. 在……上面看
D. 上下打量

2. If you go home late, you should tell your about it.

[ ]

A. father and mother
B. teachers
C. children
D. classmates

3. Good web pages for children can .

[ ]

A. be a waste of time
B. help them with their studies
C. do homework for them
D. make life difficult

4. According to the passage, which of the following is true?

[ ]

A. Tell the truth, even when you are wrong.
B. Keep some animals to kill them.
C. Look down on new ideas.
D. Everything on the Internet is good for children.

5. The passage mainly (主要地) tells us how to .

[ ]

A. care for others
B. do more at school
C. be top students
D. use the Internet

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Mr. Black was working in a factory in a big town. He liked 　1　 very much, and was very good　2　 it. When he was free, he　3　 down to a small river behind the factory and tried 　4　 some fish, but there were very few there, 　5　 the water wasn’t clean. One summer he went to the seaside during his holiday and stayed at a small cheap hotel.

“I have never fished in the 　6　 before.” He thought. “It will be more interesting than fishing in our river.”

　7　 first he caught a lot of fish and was very 　8　 . He gave them to the hotel and they cooked them for guests, and he enjoyed himself very much. After　9　, he did this every day. But 　10　 he got his bill(账单) at the end of the week, he saw it, “For oil（油） to cook fish(7 days), 70 dollars（美元）.”

1.

A．fishing　

B．drawing

C．singing

D．lying

2.

A．in　　　

B．on　　　

C．at

D．with

3.

A．lay

B．waited

C．sat

D．looked

4.

A．to watch

B．to eat

C．to find

D．to beat

5.

A．when

B．since

C．after

D．because

6.

A．river

B．sea

C．lake

D．pool

7.

A．On

B．In

C．At　　　　

D．For

8.

A．sad

B．worried

C．happy

D．sorry

9.

A．that

B．this　　　

C．eating

D．thinking

10.

A．after

B．when

C．how

D．why

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任选一题作文。(50分)
(1)题目：我身边的
要求：①先在横线上填写合适的词语，把题目补充完整，然后作文。
②除诗歌外，文体不限。600字左右。
③文中不得出现真实的人名、校名、地名。
(2)谈下面材料，然后作文。
路边长看一株雏菊，一个小女孩每天都来给它浇水。然而有一天，小女孩不来了。雏菊开姑担心起来，它将从哪里获得维持生命的水?“总会有办法的”。雏菊鼓励自已说。它闭上眼睛，陷入了深思……它开始努力向下生长它的根。它的根向泥土下越扎越深，终于从深深的泥土下品尝到清凉而甘甜的水。日子一天天过去。雏菊长得越来越茁壮，开出新的花朵。
要求：①根据材料寓意，任选一个角度怍文，题目自拟。
②除诗歌外，文体不限。600字左右。
③文中不得出现真实的人名、校名、地名。

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Mr. Black was working in a factory in a big town. He liked 　1　 very much, and was very good　2　 it. When he was free, he　3　 down to a small river behind the factory and tried 　4　 some fish, but there were very few there, 　5　 the water wasn’t clean. One summer he went to the seaside during his holiday and stayed at a small cheap hotel.
“I have never fished in the 　6　 before.” He thought. “It will be more interesting than fishing in our river.”
　7　 first he caught a lot of fish and was very 　8　 . He gave them to the hotel and they cooked them for guests, and he enjoyed himself very much. After　9　, he did this every day. But 　10　 he got his bill(账单) at the end of the week, he saw it, “For oil（油） to cook fish(7 days), 70 dollars（美元）.”

【小题1】

A．fishing　

B．drawing

C．singing

D．lying

【小题2】

A．in　　　

B．on　　　

C．at

D．with

【小题3】

A．lay

B．waited

C．sat

D．looked

【小题4】

A．to watch

B．to eat

C．to find

D．to beat

【小题5】

A．when

B．since

C．after

D．because

【小题6】

A．river

B．sea

C．lake

D．pool

【小题7】

A．On

B．In

C．At　　　　

D．For

【小题8】

A．sad

B．worried

C．happy

D．sorry

【小题9】

A．that

B．this　　　

C．eating

D．thinking

【小题10】

A．after

B．when

C．how

D．why

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