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题目列表(包括答案和解析)

(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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中学生上网一直是备受关注的话题,你班就此组织了一次主题班会,以下是几同学的观点,请仔细阅读并完成信息记录卡,一空一词。
Li Hua: Surfing the Internet is very exciting. We can do lots of things, such as playing games, listening to music, chatting with our friends and so on, I really enjoy it.
Wang Gang: I like surfing the Internet, too. Because I can learn a lot from it. I can get the latest news all over the world. I also can find the information I need so that I can spend less time on my homework.
Zhang Jie: It’s hard to say. I agree that the Internet is helpful to our study. But it’s not right to spend too much time on the games. And some information on the Internet is bad for our mind. What’s more, surfing too much does harm to our eyes. In a word, we should use the Internet in a right way.

Names
Opinions
Li Hua
◆play games      ◆listen to music      ◆chat with ___61  
Wang Gang
◆get the latest news ◆get useful    62    ◆do homework    63  
Zhang Jie
◆be helpful to our study           ◆don’t spend too much time on the games
◆be bad for our mind and    64    ◆use the Internet    65   

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中学生上网一直是备受关注的话题,你班就此组织了一次主题班会,以下是几同学的观点,请仔细阅读并完成信息记录卡,一空一词。

Li Hua: Surfing the Internet is very exciting. We can do lots of things, such as playing games, listening

to music, chatting with our friends and so on, I really enjoy it.

Wang Gang: I like surfing the Internet, too. Because I can learn a lot from it. I can get the latest news

all over the world. I also can find the information I need so that I can spend less time on my

homework.

Zhang Jie: It’s hard to say. I agree that the Internet is helpful to our study. But it’s not right to spend too

much time on the games. And some information on the Internet is bad for our mind. What’s

more, surfing too much does harm to our eyes. In a word, we should use the Internet in a right

way.

Names

Opinions

Li Hua

◆play games      ◆listen to music      ◆chat with ___61  

Wang Gang

◆get the latest news ◆get useful    62    ◆do homework    63  

Zhang Jie

◆be helpful to our study           ◆don’t spend too much time on the games

◆be bad for our mind and    64    ◆use the Internet    65   

 

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学校将为美国交流生举办告别晚会,请你以Amy的名义向校长推荐Daniel为这次活动的组织者。请参照Daniel的个人情况,写一篇80词左右的推荐信,信中不要出现自己的真实信息。开头已经给出,不计入总词数。

    Star sign:双鱼座(Pisces)

    Characteristics:自信,随和,精力充沛,有创造性

    Favourite colour:绿色

    Reason:使人精力充沛,是新生和生长之色

    Experience:去年成功组织了“校园明星”活动(Super Stars in Campus)

2nd November

Dear Principal,

I am writing to recommend Daniel to be the organizer of the farewell party for the American exchange students.____________________________________________________________

_____________________________________________________________________________

_____________________________________________________________________________

_____________________________________________________________________________

    (请将内容写在答题卷指定位置)

Yours sincerely

Amy

 

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     中学生上网一直是备受关注的热点话题。某班就这一话题组织了一次主题班会。以下是几位同学
的观点,请仔细阅读下面内容,完成信息记录卡。
     Li Hua: Surfing the Internet is very exciting. We can do lots of things, such as playing games listening
to music, chatting with our friends and so on. I really enjoy it.
     Wang Gang: I like surfing the Internet,too. Because I can learn a lot from it. I can get the latest news all
over the world. I also can find the information I need so that I can spend less time on my homework.
      Zhang Jie: It's hard to say. I agree that the Internet is helpful to our study. But it's not right to spend too
much time on the games. And some information on the Internet is bad for our mind. What's more, surfing too
much does harm to our eyes. In a word, we should use the Internet in a right way.
Names Opinions
Li Hua ◇play games
◇listen to music
◇chat with 1______
Wang Gang ◇get the latest news
◇get useful 2______ 
◇do homework 3______ 
Zhang Jie ◇be helpful to our study
◇don't spend too much time on the games.
◇be bad for our mind and 4______ 
◇use the Internet 5______ 

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