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为探究植物细胞膜的透性,某同学以红甜菜根(液泡中含有花青素)进行下列实验:
A.将不同切片放在不同温度的蒸馏水中处理1分钟后取出。
B.再分别放在清水中浸泡1小时而获得不同的切片浸出液。
C.测量这些溶液的花青素吸光度,得结果如下图。

请回答以下问题:
(1)上述实验操作步骤的叙述存在着一个明显的不足,没有遵循实验设计的    原则。请你对上述实验中的不准确的操作重新进行叙述:            
(2)由上图中的曲线你可以得出的结论是                    
(3)已知物质A能促进细胞膜上载体的活性。有人认为:经过不同温度的处理是影响了细胞膜上运载花青素的载体的活性。请你借助上述材料设计实验证明该观点是否正确。
材料用具:略。
实验步骤:
                                                                   
                                                                  
                                                                   
(2)预测结果及结论:
                                                                   
                                                                   
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完形填空

 Mark Twain, the famous American writer was travelling in France. He 1 by train to Dijon. He was tired and  2  to sleep. He asked the conductor(乘务员)to  3  when the train   4 to Dijon. But first he explained he was a very heavy sleeper.I probably will protest loudly when you  5  to wake me up, he said to the conductor. But do not take any notice, just  6  me off the train.

 Then Mark Twain went to sleep. Later, when he woke up, it was night time and the train had reached Paris already. He realized at once that the conductor  7  to wake him up at Dijon. He was very  8  . He  9  to the conductor and began to  10  him. I was never so angry in all life. Mark Twain said.

 The conductor looked at him calmly you are not half so angry as the American I put off the train at Dijon. he said.

ABCD中选择最佳答案以完成短文:

                                                                                                                       

[  ] 1A.    were going

  

B has gone

  

C had gone

  

D was going

  

[  ]    2A wanted

  

B has wanted

  

C wants

  

D was wanting

  

[  ]    3A get him up

  

B pick him up

  

C wake him up

  

D put him    up

  

[  ]    4A got

  

B come

  

C reached

  

D arrived

  

[  ]    5A will try

  

B try

  

C is trying

  

D was trying

  

[  ]    6A bring

  

B take

  

C put

  

D go

  

[  ]    7A forgot

  

B remembered

  

C remember

  

D had forgotten

  

[  ] 8A.    angry

  

B Frighten

  

C tired

  

D surprised

  

[  ] 9A.    keep up with

  

B comes up to

  

C ran up

  

D ran away from

  

[  ]10A.    cry out

  

B shout at

  

C talk about

  

D speak at

  
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