Step 1 Review第一步 复习 1. (让学生尽可能多地说出他们所知道的运动名称.) T:In last lesson, we discussed many sports that are our favorites. Do you remember them? What are they? Please tell me the sports names you know. S1: Basketball. S2: Table tennis. S3:- 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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如图甲表示某生物膜结构,图中A、B、C、D、E、F表示某些物质,a、b、c、d表示物质跨膜运输方式。图乙和图丙表示物质运输曲线,请据图回答:


(1)若图甲是癌细胞的细胞膜,则膜上含量较正常细胞减少的物质是[  ]    
(2)若图甲是线粒体膜,b和c过程运输的气体分别是    。b、c运输方式符合图    所表示的物质运输曲线。
(3)若图甲表示人体红细胞膜,则表示Na、K运输的分别是图中      。Na、K的运输方式符合图    所示曲线。
(4)已知红细胞吸收葡萄糖是协助扩散,而有人认为小肠上皮细胞以主动运输的方式吸收葡萄糖,请设计实验加以确定。
①实验步骤:
第一步:取甲、乙两组生理状况相同的小肠上皮细胞,放入适宜浓度的含有葡萄糖的培养液中。
第二步:甲组细胞给予正常的呼吸条件,         
第三步:                
②预测实验结果并分析:
a.若甲、乙两组细胞对葡萄糖的吸收速率基本相同,则         
b.                                

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阅读短文,在其后空白处写出各单词的正确形式。单词的第一个字母已经给出。

    The worst traveler in the world was Paul of San Francisco. Once he f____1. from the U.S. to his hometown in Italy to see someone at home. The plane made a one-hour stop to get oil at an airport in New York. Paul thought he was in Rome. C____2., he got off the plane.

    When nobody was there to meet him, Paul thought maybe the heavy t____3. made his friends late. While looking for their address, Paul found that the old “Rome”had changed a lot. He found many high m____4. buildings instead of old ones. He also found that many people spoke English but not Italian and that many street signs were w____ 5. in English.

    Paul knew very l____6. English. So he asked a policeman in Italian the way to the bus station. He happened to meet a policeman who was also born in Italy and answered in the same l____7..

    After twelve hours’ traveling round on a bus, the driver handed him over to a____8. policeman. But this time, this policeman could only speak English. So paul asked the policeman why the Rome police employed(雇佣)so many people who spoke English as policemen.

    Paul didn’t b____9. he was in New York when he was told so. To get him on a plane to Italy, he was s____10. to the airport in a police car.

 

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根据对话内容,填写适当单词补全对话(每空0.5 分,共5分)

A: 1.____  me, could you ___2.______  me the way to the nearest book shop, please?

B:Certainly. Go along this road and turn right ____3.____ the traffic ____4.___ .

Then walk on __5.____ you reach the second crossing. And then turn left. You will see a bridge. Go across the bridge. You will find the shop __6.__ the right. It's __7.__  the post office __8.____ the fruit shop. You can't _9.___ it.

A:Thank you very much.

B:You're ___10.___ .

 

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补全对话

A:Hello,Mrs.White!

B:Hello,Mrs.Wu!

A:Are you going to do some shopping?

B:Yes.What about you?

A: 1 It’s said(据说) the things in the new market are nice and cheap.I want to go to there. 2  

B:That’s good. 3 I’m busy now.A few Chinese friends will come to see me in an hour.I’m afraid  I can’t be back before they come.

A:It doesn’t matter.We can go when we are free.

B:By the way, 4  I haven’t been there yet.

A:It’s on the other side of the river.It’s a little far from here.

B:How long will it take me to get there by bike?

A:Half an hour. 5 It will take you right there.

B:Thanks a lot.See you!

A:See you!

 

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