练习册

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    将学生分成七组.每组选定本组的话题.可以从以下话题选择.也可自拟话题:Movie, Music, Food, Sports, Clothes, TV show etc. 【查看更多】

     

    题目列表(包括答案和解析)

    （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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    下面你将听到10组对话，每组对话都有一个问题。根据对话内容，从每组所给的三A、B、C三个选项
    中找出能回答所提问题的最佳选项。
    1. Did the woman know who won the match?
    A. It's hard to say.
    B. No, she didn't.
    C. Yes, she did.
    2. Where is the woman from?
    A. New York.
    B. England.
    C. London. 
    3. Where are the two speakers?
    A. In a classroom.
    B. On a farm.
    C. In a dining room.
    4. What's Li Ying's son?
    A. He is an engineer.
    B. He is a doctor.
    C. He is a cook.
    5. What kind of music does the man like?
    A. Jazz.
    B. Rock music.
    C. Pop music.
    6. Who gave the party for the girl?
    A. her aunt.
    B. He friend.
    C. Her mother.
    7. What is the man probably going to do?
    A. To take a train.
    B. To take a taxi.
    C. To take a bus.
    8. What's wrong with Mike?
    A. He hurt his foot.
    B. He hurt his leg.
    C. Nothing was wrong with him.
    9. What are they doing?
    A. They are singing songs.
    B. They are walking.
    C. They are making a phone call.
    10. Why hasn't Jane received the email?
    A. Because she is ill.
    B. Because she is too tired.
    C. Because here computer doesn't work.

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    下面你将听到十组对话，每组对话都有一个问题。根据对话内容，从每组所给的A、B、C三个选项
    中找出能回答所提问题的最佳选项。
    1. What can Mike do?
    A. He can ride a bike.
    B. He can swim.
    C. He can drive a car.
    2. How many chairs are there in Betty's classroom?
    A. 30.
    B. 45.
    C. 50.
    3. What does the woman want to do?
    A. To read some books.
    B. To borrow some books.
    C. To buy some newspapers.
    4. Why didn't Tom come to school yesterday?
    A. His father was ill.
    B. He was ill.
    C. His mother was ill.
    5. What's the weather like now?
    A. Cloudy.
    B. Rainy.
    C. Snowy.
    6. What are they going to make for Jack?
    A. A cake.
    B. A toy.
    C. A model ship.
    7. Where is Jerry's T-shirt?
    A. On the bed.
    B. On the table.
    C. In the living room.
    8. What's the man going to do?
    A. To see a film.
    B. To hold a party.
    C. To have a swim.
    9. When will the speakers meet?
    A. At 6:30.
    B. At 7:00.
    C. At 7:30.
    10. Where's the woman from?
    A. Australia.
    B. Japan.
    C. China.

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    面你将听到八组对话，每组对话都有一个问题。根据对话内容，从每组所给的三个选项中找出能
    回答所提问题的最佳选项。
    1. What time is it now?
    A 9:15
    B. 9:30
    C 9:45
    2. What are they talking about?
    A. The world's population.
    B. The countries in the world.
    C. The continents in the world.
    3. Where are they talking?
    A. In a library.
    B. In the clothing shop.
    C. In a post office.
    4. When did the man take his coat to the washing shop?
    A. On Tuesday.
    B. On Wednesday.
    C. On Thursday.
    5. How is the weather?
    A. Windy.
    B. Rainy.
    C. Sunny.
    6. What is the woman's idea?
    A. She likes English better than French.
    B. She thinks French is more interesting than English.
    C. She doesn't agree with the man at all.
    7. How much should the man pay if he wants to buy two yellow bags?
    A. 10 yuan.
    B. 13 yuan.
    C. 16 yuan.
    8. What does the woman tell the man to do?
    A. Drink some water.
    B. Stay in bed.
    C. Take some medicine.

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    完成句子 按所给的汉语，用英语完成下列句子，并将答案写在答题卡标有题号的横线上。（本大题共9分，每小题1.5分）
    【小题1】周末他宁可去爬山，也不愿去徒步旅行。
    He ______________________________________ than hiking at weekends.
    【小题2】多数人不容易戒掉自己的坏习惯。
    It is not easy _______________________________________ their own bad habits.
    【小题3】我们都难以想象这个小孩处理这样的问题有多大的困难。
    We can’t imagine the great difficulty the child has _________________________________.
    【小题4】开始两个月这些外国学生不适应这儿的生活。
    These foreign students _____________________________ the life here in the first two months.
    【小题5】他的新书密切关注了青少年和他们的家长之间的沟通技巧。
    His new book _______________________ the skills of the communication between teenagers and their parents.
    【小题6】我想知道你的收音机买了有多久了。
    I wonder how long _______________________________.

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