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（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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将汉语翻译成英语，每空一词。

1.尽管大雨倾泻不止，但战士们却没有放弃训练。

________ the heavy rain kept ________ down, the soldiers didn’t　 up their training.

2.当今世界面临的最大问题之一是世界人口增长越来越快。

One of the greatest 　　　of the world today is that the world’s population is growing ________ and ________.

3.我们很长时间没见面了。

We haven’t ________ each other ________ a long time.

4.化学制品对环境有害。

Chemicals are ________ ________ the environment.

5.除非明天下雨,否则我将去钓鱼。

________ it　　 tomorrow, ________ I’ll go　　 .

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完形填空

　　Almost everybody likes to play．All over the world men and women, boys and girls enjoy sports．Sports help to keep people 　　1　　．They help people to live 　　2　　．

　　Sports change 　　3　　 the season．People play different games in winter and summer．Sailing(航海)is fun in warm weather, 　　4　　 skating is good in winter．

　　Games and sports often 　　5　　 the work people do．The Arabs are famous 　　6　　 their sports events with camels(骆驼)．Hunting and 　　7　　 are good sports, but millions of people hunt and fish for 　　8　　．

　　People from different countries may not be able to know each other, 　　9　　 after a game on the sports field, they often become good friends．Sports help to train(培养)a person’s character(性格)．One learns to fight hard, 　　10　　 with pride and lose with grace(体面)．

(1)


[　　]
A．	health
B．	healthy
C．	healthily
D．	helpful

(2)


[　　]
A．	happily
B．	happy
C．	happiness
D．	happier

(3)


[　　]
A．	or
B．	of
C．	on
D．	with

(4)


[　　]
A．	since
B．	or
C．	while
D．	when

(5)


[　　]
A．	grows of
B．	grows out
C．	grow out of
D．	grow by

(6)


[　　]
A．	to
B．	for
C．	by
D．	at

(7)


[　　]
A．	fishing
B．	fish
C．	to live
D．	fished

(8)


[　　]
A．	life
B．	live
C．	to live
D．	living

(9)


[　　]
A．	but
B．	and
C．	or
D．	still

(10)


[　　]
A．	won
B．	winning
C．	wins
D．	to win

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完形填空

　　We were going to play a team from a country school． They didn't come until the game time arrived．They looked 　　1　　 than we had thought．They were wearing dirty blue jeans(仔裤) and looked like farm boys．We even thought that they had never seen a basketball before．

　　We all sat down．We felt that we didn't 　　2　　 any practice(训练)against a team like that．

　　It was already so late that no 　　3　　 could be given to them for a warm-up．

　　The game began．

　　One of our．boys 　　4　　 the ball and he shot(掷)a long pass to our forward (前锋)．From out of nowhere a boy in a dirty T-shirt 　　5　　 the pass and with a beautiful form(姿势)he shot and got two points(分)．

　　They 　　6　　 us．

　　Then they got another 　　7　　 of points in a minute．

　　Soon it was all over．The country team 　　8　　 us．

We certainly learned that even though a team is good，there is usually another 　　9　　 a little better．But the important lesson learned was：One can't tell a man，or a team，by the 　　10　　．

(1)


[　　]

(2)


[　　]

(3)


[　　]

(4)


[　　]

(5)


[　　]

(6)


[　　]

(7)


[　　]

(8)


[　　]

(9)


[　　]

(10)


[　　]

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—Where ______ the lion come from?

—_______.

A.　is；America B.　does；American 　C.　does；America

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