题干

为研究根背光生长与生长素的关系,将水稻幼苗分别培养在含不同浓度生长素或适宜浓度NPA(生长素运输抑制剂)的溶液中,用水平单侧光照射根部(如下图),测得根的弯曲角度及生长速率如下表:

据此实验的结果,不能得出的结论是(  )

A:根向光一侧的生长速率大于背光一侧

B:生长素对水稻根生长的作用具有两重性

C:单侧光对向光一侧生长素的合成没有影响

D:单侧光照射下根的背光生长与生长素的运输有关

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答案(点此获取答案解析)

C

同类题3

阅读下面的材料,根据要求写一篇不少于800字的文章。

    小王在电影厂大院里长大。父亲老王为人低调谦和,从影六十年,是演技精湛的老戏骨。儿时的小王经常跟随父亲出入片场但并不喜欢表演,加上长相寒碜,“歪瓜裂枣”似的,父亲认为他将来只能搞个摄影、剧务什么的。十七岁的小王插队下乡,专门喂猪,心里却滋生了演员梦,十八岁返城连考北京八个艺术团队,均告失败。父亲看到儿子如此执着,就找人帮没有任何演艺基础只擅长喂猪的小王排了个喂猪的小品,小王凭着完美逼真的表演走进演艺界。

    前十年,小王一直跑龙套,当配角。母亲让他改行,可小王和父亲当年一样,口头禅是“甘当绿叶”。

    后来终于凭借一部影片一举成名。接下来就大放异彩,好片不断,获奖无数,甚至夺得国际大奖。小王一时心潮澎湃,大胆接了一个“皇帝”的角色,结果被观众评为当年最差男主角。父亲严厉批评了他,认为他适合演那种“接地气的,贴近生活的小人物”,同时告诫他:“演员,在荧屏里演的是人,在生活中没理由不像人。”小王谨遵父教,从此,对选角色变得很谨慎,常常因琢磨如何演得接地气而失眠,生活中的小王也更加低调谦和,结婚二十多年,夫妻举案齐眉,相敬如宾。

    对小王的生活工作经历,你有何思考?请阐明你的看法。

    要求:综合材料内容及含意,选好角度,确定立意,明确文体,自拟标题;不要套作,不得抄袭,不得泄露个人信息。

同类题4

阅读理解

    Everybody hates it, but everybody does it. A recent report said that 40%of Americans hate tipping. In America alone, tipping is a $ 16 billion-a-year industry. Consumers acting politely ought not to pay more than they have to for a given service. Tips should not exist. So why do they? The common opinion in the past was that tips both rewarded the efforts of good service and reduced uncomfortable feelings of inequality. And also, tipping makes for closer relations. It went without saying that the better the service, the bigger the tip.

    But according to a new research from Cornell University, tips no longer serve any useful function. The paper analyzes numbers they got from 2,547 groups dining at 20 different restaurants. The connection between larger tips and better service was very weak. Only a tiny part of the size of the tip had anything to do with the quality of service.

    Tipping is better explained, by culture than by the money people spend. In America, the custom came into being a long time ago. It is regarded as part of the accepted cost of a service. In New York restaurants, failing to tip at least 15% could well mean dissatisfaction from the customers. Hairdressers can expect to get l5%-20%, and the man who delivers your fast food $ 2. In Europe, tipping is less common. In many restaurants the amount of tip is decided by a standard service charge. In many Asian countries, tipping has never really caught on at all. Only a few have really taken to tipping. According to Michael Lynn, the Cornell papers' author, countries in which people are more social or outgoing tend to tip more. Tipping may reduce anxiety about being served by strangers. And Mr. Lynn says, “In America, where people are expressive and eager to mix up with others, tipping is about social approval. If you tip badly, people think less of you. Tipping well is a chance to show off.”