Step 1 Review 第一步 复习 1.(通过师生互动.复习学过的特殊疑问句.) (1)T : What’s your name? S1: My name is - T : Where are you from? S1: I’m from - T : What’s your telephone number? S1: My telephone number is - (教师给予肯定和表扬.提问另一个学生.) T : Excuse me. What’s your name? S2: My name is - T : How old are you? S2: I’m - T : What class are you in? S2: I’m in - (2)(教师接下来请S3针对S1或S2的情况进行问答.) T : What’s his/her name? S3: His/Her name is - T : Where is he/she from? S3: He/She is from - T : How old is he/she? S3: He/She is - T : What class is he/she in? S3: He/She is in - T : What’s his/her telephone number? S3: It’s - 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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(10分)生长素的主要作用是促进细胞纵向伸长,其作用机理如图所示,请回答下列问题:

(1)生长素作用的第一步是与细胞膜上的受体结合,形成“激素—受体复合物”,这一过程体现了细胞膜的_________功能。
(2)被激活的“激素—受体复合物”能引起内质网释放Ca2 + , Ca2 +促使细胞内的 H+        的方式运往细胞外,增加了细胞壁的延展性,使细胞壁对细胞的压力减小,导致细胞吸水、体积增大而发生不可逆增长。细胞在生长过程中体积变化最大的细胞器是________。实验发现,细胞在持续生长过程中,细胞壁的厚度能基本保持不变,出现这种现象的原因是由于_____________(填细胞器)为细胞壁添加了新的成分。
(3) Ca2 +还能激活细胞中的转录因子,它进入细胞核后,能引起____酶催化 mRNA 的合成。
(4)生长素促进根系生长的最适宜浓度要比茎低得多,稍高浓度的生长素能促进乙烯的生物合成,从而抑制了根的伸长,这说明生长素的作用具有__________。
(5)科学家研究发现紫外线可以抑制植物生长,原因是紫外线增加了植物体内吲哚乙酸氧化酶的活性,从而促进了生长素氧化为3—亚甲基氧代吲哚,而后者没有促进细胞伸长的作用。现在提供生长状况相同的健康的小麦幼苗若干作为实验材料,请完成下列实验方案,以验证紫外线抑制植物生长与生长素的氧化有关。
步骤 1 :将小麦幼苗平均分为甲组和乙组。
步骤 2 :给予甲组适宜的可见光光照,给予乙组_______________________光照。
步骤 3 :观察两组幼苗的________________,并测量___________的含量。
预测实验结果: ______________________________________________________。

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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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补全对话(共5分)

  从方框内选择恰当的句子完成下面的对话。(共5分,每小题1分)

A. A table for two?

B. What can I do for you?

C. My I take your order now?

D. Excuse me. Could we have some coffee, please?

E. This way, please.

F. Anything else?

G. What would you like to drink?

  Waiter: Good morning, madam.

  Gina: Good morning.

  Waiter: 1._____________

  Gina: Yes. Can we have table by the window?

  Waiter: OK. 2. _____________

  ( At the table )

  Waiter: Here's the menu. 3.__________

  Gina: Yes. We'd like chicken with potatoes, beef with onions and some rice.

  Waiter: 4.__________

  Gina: Orange juice.

  Waiter: 5.________

  Gina: No, that's all. Thank you.

 

 

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