题干

如图1是将含有生长素的琼脂块放在切去尖端的胚芽鞘一侧,一段时间后测定的胚芽鞘的弯曲情况(弯曲角度用α表示);图2是生长素浓度对胚芽鞘生长的作用示意图。下列相关叙述错误的是(    )


A: 只用图1实验不足以证明生长素有促进生长的作用

B: 琼脂块中生长素浓度不同,但可能形成相同的α

C: 琼脂块中生长素浓度为b时,α最大

D: 琼脂块中生长素浓度为d时,胚芽鞘向左侧弯曲

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A,D

同类题1

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太阳和霓虹灯

       ①这是我们来到北京的第三天,这一天的任务是采访三位文化艺术界名人。

       ②早晨,我们先来到一位著名女演员家里。用北京人的土话说,这位“大腕”现在正“火”。从见面到讲述完自己的奋斗经历,她的眼神一直是冷漠孤傲的。讲述完毕,“大腕”严肃地说:“你们的文章写好以后一定要让我过目。”快出门的时候,她又叮嘱我们:“如果没有把握写好的话,我可以为你们推荐作者。”我们谢绝了她的好意。

       ③第二个采访对象是某电视台节目主持人。见面地点定在京广大厦,这是主持人要求的。从顶层临窗的位置往下看,大街上的人如蚂蚁一样渺小,马上使人产生一种君临天下的感觉。主持人也的确给这环境争气,不时打着标准的领袖手势,言语间也常常引经据典。他偶尔也有卡壳的时候,说出文章中的一句甚至半句话后愣怔片刻,然后一挥手说:“你们回去再查吧,这么简单的东西还用从头到尾说完吗?”这使我们对他的“敬仰”又增加了一分。

       ④来到季羡林老人家里已是傍晚了。秘书出来挡驾,为难地说,老人今天已接待过几个外国代表团了,最好明天再来吧。我们的日程安排得很紧,明明知道老人很累,依然抱着试一试的态度。(甲)秘书进去请示,老人竟答应了。秘书把时间限定为20分钟。

       ⑤老人的相貌、衣着和我们想象的竟非常吻合,这可能因为那个真实的故事:几年前一个新生入学,看见路边一个淳朴得像农民一样的老者,以为是工友,便让老人帮他看管一大堆行李。这位老人欣然同意,并尽职看管达半个小时之久。几天以后,北京大学举行新生入学典礼,这个学生惊讶地发现,坐在主席台正中的,被介绍为北京大学副校长的,正是那天为自己看管行李的老者。

       ⑥来之前就听说老人有两套房子,我们展开俗人的想象,非常羡慕。但看了才知道,室内空间大部分被书占据着,而供老人活动的空间极小。老式家具,陈设简单、朴素。

       ⑦虽然某些问题问得幼稚,但在交谈的过程中,我们每提出一个问题,(乙)老人都要思考片刻,有两次竟手抚额头陷入长时间的思考。老人留给我们最深刻的印象便是认真思考,这可能已经成为老人生活中的一种习惯。由此可以看出老人的两种美德:一、尊重知识,用老人的话说就是“板凳甘坐十年冷,文章不说半句空”。二、尊重别人,用老人的话说就是“我的自知之明有些过了头”。

       ⑧一个多小时眨眼之间就过去了。采访结束,老人一直把我们送到门口,一一握手告别。

       ⑨紫禁城的傍晚很美。太阳悬挂在地平线上,光线柔和。它是至高无上的,但在某些时候却情愿寻求平等,因为它知道这种姿态更有利于交流。都市的霓虹灯也亮了起来,五彩缤纷并且极富动感,竭力招揽着人们的目光。太阳和霓虹灯同时出现,看上去竟不觉得有什么不和谐,也许因为它们都发光吧。

同类题4

阅读理解

    You may be familiar with the following famous people, but have you heard of their graduation speeches, in which they either share their unforgotten experiences or give you some great inspiration(启迪).

    Michael Dell, University of Texas at Austin

    And now you've accomplished something great and important here, and it's time for you to move on to what's next. And you must not let anything prevent you from taking those first steps. ... You must also commit to the adventure. Just have faith in the skills and the knowledge you've been blessed (赐予)with and go.

    J.K. Rowling, Harvard University

    Half my lifetime ago ,I was striking an uneasy balance between my ambition and the expectation from my parents who were not rich...But what I feared most for myself at your age was not poverty(贫穷), but failure. The fact that you are graduating from Harvard suggests that you know little about failure, you might be driven by a fear of failure quite as much as a desire for success.

    Steve Jobs, Stanford University

    Sometimes life's going to hit you in the head with a brick. Don't lose faith...Your work is going to fill a large part of your life, and the only way to be truly satisfied is to do what you believe is great work, and the only way to do great work is to love what you do. If you haven't found it yet, keep looking, and don't settle.

    Bill Gates, Harvard University

    We need as many people as possible to have access to the advanced technology to lead to a revolution in what human beings can do for one another. They are making it possible not just for national governments, but for universities ,smaller organizations, and even individuals to see problems, see approaches and deal with the world's inequities(不公平)like hunger, poverty, and so on.