在学生表达过程中.教师可以把report中呈现的形容词写到黑板上. 查看更多

 

题目列表(包括答案和解析)

书面表达。
     你在求学的过程中肯定遇到过很多好老师,你最喜欢哪位呢?请你以The Teacher I Like
Best为题, 用英语写一篇短文,参加美国杂志Weekly Reader的征文活动。
     内容可涉及:他(她)是谁、教什么学科;你喜欢他(她)的原因。可以适当发挥。
     要求:1. 80-100 词;
                 2. 文中不得出现真实姓名及校名,老师姓名统一使用Mr./Mrs./Miss XX,
     例如:Mr. Ma。
     _________________________________________________________________________
____________________________________________________________________________
____________________________________________________________________________

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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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】阅读《塑料瓶装水真的干净吗》完成下面题目(7分)
①出门在外,口渴的时候我们都习惯买一瓶水喝,瓶装水给我们的印象是干净和方便,尤其是高档瓶装水都会标榜自己“出身清白”,“从未受到过人类污染”。例如,“王岛云雨”产自澳大利亚塔斯马尼亚岛,那里号称拥有世界上“最干净的空气”,雨水自然清洁无比;“公元前1万年”产自号称“地球上最古老的水源”——加拿大卑诗省沿岸的冰川,水质更是纯正无比。然而,科学家指出,塑料瓶装水也有可能“不干净”。
②英国化学研究人员威廉·肖迪克表示,装饮用水的塑料瓶生产过程就有污染隐患,因为在制造瓶子的过程中,会使用含有锑元素的化合物作催化剂,随着塑料瓶的成型,锑元素也进入了塑料中。塑料瓶可能会持续向瓶中的水溶解重金属元素锑,这种元素长期积聚在体内可能危害健康。威廉·肖迪克对当地的15种热销瓶装水进行化学检验,结果发现天然地下水中的锑含量是万亿分之一,而刚出厂的瓶装水的锑含量平均为万亿分之一百六十。时间越长,塑料瓶中的锑元素在水中的溶解量越大,这个过程就像泡茶一样。出厂3个月后,瓶装水中的锑元素的含量竟然增加了一倍。然而,现在市场上大多数瓶装水包装上注明的保质期大多是24个月。另外,温度越高,锑元素在水中的溶解量越大,而人们对瓶装水需求量较大的季节是温度高的夏天。肖迪克表示,虽然摄入极少量的锑元素不会导致人生病,但是大量摄入则会诱发呕吐,甚至可能致命。
③美国哈佛大学的研究人员米歇尔等人发现,不少塑料瓶在加工过程中会加入名为“双酚A”(BPA)的化学物质。这种化学物质与出生缺陷、发育问题、心脏病和糖尿病患病风险高有关联。专家对它可能对人体健康造成的影响表示担忧,而一些国家已将该物质正式列为有毒物质。
④此外,荷兰研究者发现,瓶装矿泉水经常被细菌和真菌污染,污染的瓶装矿泉水对健康个体致病的危险可能有限,但对于免疫功能低下的病人和婴儿,则有更高的感染危险。
⑤英国“水与环境管理协会”的执行主席尼克·里夫斯还表示,瓶装水对环境的污染也不容忽视。全世界每年用于制造塑料瓶的塑料为270万吨,这些塑料的原料大多是从石油中提取的,仅在美国,制造这些塑料瓶就要消耗150万桶石油,这些石油可以供10万辆汽车使用一年。86%的塑料水瓶最后都变成了垃圾,需要400年至1000年才能降解。这些塑料垃圾在燃烧时会产生有毒气体和含有重金属的灰烬。
(摘自2011年5月《知识就是力量》,略有删改)
A.随着温度增高,时间增加,塑料瓶中的锑元素在水中溶解量会越大。
B.重金属元素锑一旦被人体摄入,就会诱发呕吐,甚至可能致命。
C.全世界每年用于制造塑料瓶的塑料为270万吨,这些塑料的原料大多是从石油中提取的。
D.专家认为,在塑料瓶加工过程中所加入的名为“双酚A”(BPA)的化学物质可能对人体健康造成影响。
【小题1】下列句中划线词语能否删去?为什么(4分)
(1)出厂3个月后,瓶装水中的锑元素的含量竟然增加了一倍。
(2)瓶装矿泉水经常被细菌和真菌污染,污染的瓶装矿泉水对健康个体致病的危险可能有限,

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中学生在成长的过程中总会遇到不同的烦恼,以下是一些学生的自述和生活老师的解决

办法,请你给予合理的配对。

1.I borrowed Jimmy’s favorite storybook last week. But I can’t find it now. I think I have left it somewhere.

2.I was criticized seriously by my Chinese teacher when I was sleeping in the class. Now I don’t like Chinese classes as before. It makes me feel embarrassed.

3.I had forgotten to turn off the mobile phone before I entered the classroom. It rang for a long time in the class. None of my classmates have criticized me, but I am upset about it now.

4.I have dreamt of volunteering to clean the city park, but I am afraid that others will laugh at me. They may think I am a cleaner.

5.I think I am creative. I always have some new ideas. And I spend lots of time trying to invent something. But my parents let me spend all the time in the school subjects..

A. If I were your Chinese teacher, I would be angry, too. So I think you should realize yourself first. Then have a talk with your teacher and tell him you won’t do that again.

B. We shouldn’t laugh at cleaners. We can’t live a clean life without them. So don’t be shy and be a volunteer as you have dreamt.

C. You’d better buy a new book for him. And then you can explain to him what has happened. D. Remember to say sorry to him.

E. According to your description, I can see that you are a very nice child. I think you can give a small speech to apologize (道歉) to them after class.

F. I think a creative child should be encouraged. Why not make a good plan with your parents? G. You can spend most time in school subjects. And in your spare time, you can try your ideas.

 

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中学生在成长的过程中总会遇到不同的烦恼,以下是一些学生的自述和生活老师的解决办法,请你给予合理的配对。

1.I borrowed Jimmy’s favorite storybook last week. But I can’t find it now. I think I have left it somewhere.

2.I was criticized seriously by my Chinese teacher when I was sleeping in the class. Now I don’t like Chinese classes as before. It makes me feel embarrassed.

3.I had forgotten to turn off the mobile phone before I entered the classroom. It rang for a long time in the class. None of my classmates have criticized me, but I am upset about it now.

4.I have dreamt of volunteering to clean the city park, but I am afraid that others will laugh at me. They may think I am a cleaner.

5.I think I am creative. I always have some new ideas. And I spend lots of time trying to invent something . But my parents let me spend all the time in the school subjects..

A. If I were your Chinese teacher, I would be angry, too. So I think you should realize yourself first. Then have a talk with your teacher and tell him you won’ t do that again.

B. We shouldn’t laugh at cleaners. We can’t live a clean life without them. So don’t be shy and be a volunteer as you have dreamt.

C. You’d better buy a new book for him. And then you can explain to him what has happened. Remember to say sorry to him.

D. According to your description, I can see that you are a very nice child. I think you can give a small speech to apologize (道歉) to them after class.

E. I think a creative child should be encouraged. Why not make a good plan with your parents? You can spend most time in school subjects. And in your spare time, you can try your ideas.

 

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