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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Ca 2+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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    中国人失掉自信力了吗
    鲁迅
    　　①从公开的文字上看起来：两年以前，我们总自夸着“地大物博”，是事实；不久就不
    再自夸了，只希望着国联，也是事实；现在是既不夸自己，也不信国联，改为一味求神拜佛，
    怀古伤今了——却也是事实。
    ②于是有人慨叹曰：中国人失掉自信力了。
    ③如果单据这一点现象而论，自信其实是早就失掉了的。先前信“地”，信“物”，后来
    信“国联”，都没有相信过“自己”。假使这也算一种“信”，那也只能说中国人曾经有过“他
    信力”，自从对国联失望之后，便把这他信力都失掉了。
    ④失掉了他信力，就会疑，一个转身，也许能够只相信了自己，倒是一条新生路，但不
    幸的是逐渐玄虚起来了。信“地”和“物”，还是切实的东西，国联就渺茫，不过这还可以
    令人不久就省悟到依赖它的不可靠。一到求神拜佛，可就玄虚之至了，有益或是有害，一时
    就找不出分明的结果来，它可以令人更长久的麻醉着自己。
    ⑤中国人现在是在发展着“自欺力”。
    ⑥“自欺”也并非现在的新东西，现在只不过日见其明显，笼罩了一切罢了。然而，在
    这笼罩之下，我们有并不失掉自信力的中国人在。
    ⑦我们从古以来，就有埋头苦干的人，有拚命硬干的人，有为民请命的人，有舍身求法
    的人，……虽是等于为帝王将相作家谱的所谓“正史”，也往往掩不住他们的光耀，这就是
    中国的脊梁。
    ⑧这一类的人们，就是现在也何尝少呢？他们有确信，不自欺；他们在前仆后继的战斗，
    不过一面总在被摧残，被抹杀，消灭于黑暗中，不能为大家所知道罢了。说中国人失掉了自
    信力，用以指一部分人则可，倘若加于全体，那简直是诬蔑。
    ⑨要论中国人，必须不被搽在表面的自欺欺人的脂粉所诓骗，却看看他的筋骨和脊梁。
    自信力的有无，状元宰相的文章是不足为据的，要自己去看地底下。
    　　　　　　　　　　　　　　　　　　　　　　　　　　　　　九月二十五日。
    【小题1】．作者批驳的观点是什么？确立的观点又是什么？（４分）
    【小题2】．文章由直接反驳转到间接反驳起过渡作用的是第几段？它在内容上是怎样承上启下的？请结合原文作答。（５分）
    【小题3】．联系全文，对“埋头苦干的人”、“拼命硬干的人”、“为民请命的人”、“舍身求法的人”的共同特征概括错误的一项是（　　）（２分）
    A．他们都是中国的脊梁。
    B．他们有确信，不自欺。
    C．他们前仆后继的战斗。
    D．他们总不为大家所知道。
    【小题4】．文章⑦—⑨段反复强调“中国的脊梁”，表达出作者怎样的思想感情？（４分）
    【小题5】．今天的中国正在各个领域展现出国民的自信力，请依照例句按要求续写。（5分）例句：杨利伟，用自信的挥手代表了中国航天科技的高度；
    续写：　　　　，                                                          ；
    　　　　，                                                          。
    他们都                                 。

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    书面表达

    今年我国西南五省市持续干旱，出现旱情。请根据提示用英文写一篇短文，词数不少于100个(所给词不纳入计数)。

    提示：干旱drought　温室效应the Greenhouse Effect　与…有很大关系have much to do with…　水的短缺the short of water

    1．我国西南五省市持续严重干旱，当地人民没有足够水可以喝，或可以用。水的短缺严重地影响了当地人民的生活。

    2．据说干旱与温室效应有很大的关系，而温室效应是由空气的污染引起的，所以我们应立刻停止污染。

    3．从这次干旱中我们懂得了很多：地球是我们的家园，保护地球就是保护我们自己！从现在开始，我们应采取措施去阻止和预防其它灾害的发生。(如，节省用水，保护森林不被砍伐，多种植树木)

    Recently, terrible drought has prevailed(盛行)in the southwest provinces and cities of our country．

    ________________________

    ________________________

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    阅读理解，阅读下面语言材料，然后按文后要求做题。

    　　Julio loves to visit his grandmother．He doesn't get to visit her very often because his family lives in a city that is six hours away．His grandmother lives in a big wooden house on a farm．It is old and looks as if it has secret hiding places．

    　　On the third Sunday of June, Julio's parents took him to his grandmother's．Since it was summer vacation, he was going to stay at grandmother's for a whole summer．Hid cousins Mario and linda would soon be arriving．They would also be staying at their grandmother's this summer．

    　　A big porch(走廊)wrapped(缠绕)around two sides of the house．Julio sat in the porch swing(秋千)．He could see the trees that circle the house．They had been planted as a windbreak(防风林)．They protected the house from the wind and blowing dirt．The house was in the middle of a large flat field．

    　　Julio watched the dirt road that led to the house．He couldn't wait for his cousins to get there．Mario was his age, and Linda was a year younger．They had fun together．Last summer they spent one whole morning making a fort out of sacks of seed(装种子的麻袋做成的堡垒)．Then Uncle Henry took them on a tractor ride．

    　　Julio remembered another time with his cousins．They had gone out to explore the fields．Julio touched an electric fence and got a shock．Then they found an old snake skin．Nothing like that ever happened at his own home!

    　　Julio could smell the dinner that his grandmother was cooking．It made him hungry．

    　　Finally he saw a cloud of dust coming up the road．“They’re here! They are here! ”He shouted．

    根据材料内容选择最佳答案。并将其标号填入题前括号内。

    (1)

    Why doesn't Julio often visit his grandmother?

    [　　]

    A．

    Because he doesn't love his grandmother．

    B．

    Because his parents don't let him visit his grandmother．

    C．

    Because his home is far away from his grandmother's．

    D．

    Because he is often ill．

    (2)

    Who is the youngest of Julio and his cousins?

    [　　]

    A．

    Lincia．

    B．

    j7L1∶l0．

    C．

    Mario．

    D．

    Henry．

    (3)

    The story tells about Julio and his cousins doing all of the following except ________．

    [　　]

    A．

    watching old movie

    B．

    taking a tractor ride

    C．

    finding a snake skin

    D．

    making a fort from seed sacks

    (4)

    How do you think Julio felt when he saw his cousins arriving?

    [　　]

    A．

    He was worried．

    B．

    Ht：was excited．

    C．

    He was angry．

    D．

    He was sad

    (5)

    After Julio cousins arrive, when would probably happen next?

    [　　]

    A．

    They would build a fort on the hill

    B．

    They would look for snake skins．

    C．

    They would climb the trees in their grandmother's yard

    D．

    They would eat dinner at their grandmother's house

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    根据短文内容回答问题。(Answer the questions according to the passage．)

    Say“No”to plastic bags

    　　In order to stop plastic pollution, China put a ban(禁令)on thin plastic bags(plastic bags thinner than 0.025 mm)．From June 1, 2008, China stopped the production, sale and use of these plastic bags．It stopped shops from giving out free plastic bags to the public and call on the consumers to adopt healthy shopping habits to protect our environment．

    Why are plastic bags so bad?

    　　China's plastic bag consumption(消费量)has rocketed to near three billion bags per day－that's about 2 for every man, woman and child－causing many tons of plastic to go to landfill sites．

    　　The bags can take between 400 and 1, 000 years to break down, and like all forms of plastic they do not biodegrade．They clog(阻碍)waterways and spoil the landscape．They also pollute the soil and water．

    　　Plastic bags also present a serious danger to animals．They often mistake them for food．Thousands of them die each year after swallowing or choking with discarded(丢弃的)plastic bags．

    　　Finally, producing plastic bags requires millions of gallons of petroleum(石油)that could be used for transportation or heating．

    What can we do?

    　　Refuse plastic bags in shops, and try to recycle or reuse the ones you do have．Buy a cloth bag/basket and keep it with you when you need to go to the shops．

    1．When did China put a ban on thin plastic bags?

    ________________________________

    2．What is this passage about?

    ________________________________

    3．What is another saying of“plastic bag consumption”?

    ________________________________

    4．What can you do if you go shopping with your mother in the supermarket?

    ________________________________

    5．Why does the writer think plastic bags are bad for the animals?

    ________________________________

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