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    15．three num. 三 【查看更多】

     

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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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         Translate the Chinese in the brackets into English to complete the sentence. (根据括号中的
    汉语意思完成句子。)
    1. __________ (不)you nor he was late for school.
    2. I like to eat__________ (饺子).
    3. Three__________ (四分之三)of the students want to go boating.
    4. In fact, he is __________ (勇敢)than me.
    5. There are four__________ (季节) in a year.

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    Three men came to London 　1　 a holiday. They came to a large hotel and took a room there. 2　 room was 　3　 the fifteeth floor.

    　　In the evening the three men went to a cinema and came 　4　 very late.

    　　“I’m sorry,” said the assistant of the hotel, “Our lifts (电梯) are not 　5　 tonight. If you 6　 want to walk up to your room. We shall make up a bed for you 　7　 the hall.”

    　　“No, no,” Tom, one of the three 　8　 , said, “No, thank you We do not want to sleep in the hall. We shall walk up to our room.”

    　　Then he turned to his 　9　 friends and said, “It is not easy to walk up to the fiftieth floor, but I know how to make it 　10　 . On our 　11　 to the room. I shall tell you some jokes (笑话), then you, Andy, sing us some songs, then you, Peter, 　12　 us some interesting 　13　 .”

    　　“All right, that’s a good idea.” the friends both agreed.

    They began to walk up to their room Tom told many jokes. Andy 　14　 some songs. 　15　 they came to the thirty eighth floor. They were tired and wanted to have a rest.　　

    “Well,” said Tom. “Now it’s 　16　 turn, Peter. After all those jokes we 　17　 and songs we listened to. Tell us a long and interesting story with a sad ending.”

    　　“All right,” said Peter, “I shall tell you a story. It is not long, 　18　 it is 　19　 sad: We 　20　 the key to our room in the hall.”

    ( )1. A. for

    B. of

    C. to

    D. with

    ( )2. A. Where

    B. Their

    C. His

    D. They’re

    ( )3. A. in

    B. at

    C. for

    D. on

    ( )4. A. home

    B. from

    C. back

    D. to

    ( )5. A. work

    B. working

    C. works

    D. to working

    ( )6. A. won’t

    B. don’t

    C. aren’t

    D. didn’t

    ( )7. A. in

    B. on

    C. at

    D. by

    ( )8. A. women

    B. man

    C. men

    D. assistants

    ( )9. A. second

    B. first

    C. one

    D. two

    ( )10. A. difficult

    B. easier

    C. easily

    D. more difficult

    ( )11. A. floor

    B. way

    C. hall

    D. lifts

    ( )12. A. say

    B. speak

    C. talk

    D. tell

    ( )13. A. story

    B. stories

    C. the story

    D. the stories

    ( )14. A. sings

    B. sang

    C. singing

    D. sing

    ( )15. A. In no time

    B. At first

    C. A moment ago

    D. At last

    ( )16. A. your

    B. you

    C. yours

    D. yourself

    ( )17. A. heard

    B. heard of

    C. heard about

    D. heard from

    ( )18. A. and

    B. or

    C. but

    D. that

    ( )19. A. real

    B. true

    C. really

    D. truly

    ( )20. A. leave

    B. are leaving

    C. put

    D. left

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    I have a good friend in my home. It is a bird. Its name is Polly. It's three. It is yellow and very beautiful (美丽). I play with it after school. My classmates-Ann and Kate often(时常) come to see it.

    　　Polly sings (唱歌) every day. I teach (教)it to sing the "ABC". Now it can sing the "ABC". I like it very much.

    请根据短文内容，选择最佳答案, 将其标号在答题卡上涂黑。（每小题1分，共5分）

    56. Who is my friend?

    A. Polly. 　                    B. Ann. 　            C. Mike. 　           D. Kate.

    57. Is Polly a bird?

    A. No, it is.            B. No, it isn't. 　          C. Yes, it is. 　             D. Yes, it isn't.

    58. How old is Polly?

    A. One. 　              B. Five. 　                   C. Three. 　                D. Four.

    59.  Who teaches (教) Polly to sing the“ABC”?

    A. I do. 　              B. You do. 　               C. She does. 　            D. He does.

    60. Where’s Polly?

    A. It’s a school.                 B. It’s in my home.

    C. It’s in the sky (天空).                D. It’s in a tree.

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    完形填空。
    　　It was seven o'clock on the morning of August 29th.The Kelly family were going to Brighton,a town
    by the sea.  
    　　"Can we have breakfast 1 we leave?"asked Gina Kelly.
    　　"No,”said her mother. “We must leave now,or the traflic(交通)will be 2 . We'll have breakfast when
    we 3 the seaside. "
    　　Gina ran downstairs. “I’m ready,"she said.    
    　　The family climbed into the 4 , and Dad started driving.In the front of the car was Mike. He was
    eleven. He didn’t talk but just 5 music. In the back of the car were Gina, her mother and Ellen. Gina was
    nine and Ellen was three.   
     　　Dad drove very fast. “You’re driving too fast,"said Mum. “You don’t have to drive so fast.It’s 6.”    
    　　Dad laughed and drove more slowly.There wasn’t 7 traffic , and they reached Brighton at nine
    o’clock. It was a sunny day, and the sea 8 very blue.    
    　　"There’s a cafe,"said Gina. “Can we have breakfast there?"    
    　　"Yes,” said Mum. They went into the cafe,and ate a very big breakfast.   
    　　"Oh dear,I am full,"said Gina. “9 can I swim when I’ve got all that food inside me?”    
    　　"Easy,"shouted Mike. “Just watch me!”He ran towards the sea,followed by Gina happily.    
    　　What a(n) 10 day it was going to be!

    (   )1. A. before    
    (   )2. A. wonderful 
    (   )3. A. move      
    (   )4. A. bus      
    (   )5. A. heard    
    (   )6. A. late      
    (   )7. A. too much 
    (   )8. A. sounded  
    (   )9. A. Where   
    (   )10. A. exciting  

    B. after      
    B. safe      
    B. leave    
    B. car        
    B. listened to  
    B. great      
    B. much too  
    B. tasted     
    B. How      
    B. boring   

    C. while    
    C. terrible    
    C. clean     
    C. train      
    C. listened   
    C. busy      
    C. too many  
    C. looked    
    C. Whether  
    C. useful   

    D. when
    D. easy
    D. get to
    D. ship
    D. heard of
    D. early
    D. many too
    D. felt
    D. Why
    D.  noisy

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