题干

下列关于生长素的叙述,正确的是(     )

A:金丝雀蘸草的胚芽鞘在黑暗条件下不能合成生长素

B:黄化豌豆幼苗切段内高浓度生长素会促进乙烯合成

C:不同细胞、器官对相同浓度生长素的敏感程度相同

D:胚芽鞘中生长素能从形态学下端运输到形态学上端

上一题 下一题 0.0难度 选择题 更新时间:2019-11-19 07:19:39

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B

同类题1

阅读下面的文字,完成小题。

    孔子的际遇,颇令人感叹。他的道德学问,为当时人所推重;他经世致用的抱负,却未曾得以放手施展。在经历了种种挫折之后,孔子似乎也有过对政治生涯的心灰意冷。但是,他对于礼乐文化的坚守与传承,却未曾有过犹豫彷徨。即便当时无法兴起礼乐以济世安民,他仍把希望寄托在将来。

    孔子一生不得志,这其中问题的症结,就在于孔子对礼乐之治的坚持与当时的政治需求不相符合。春秋末期,周王室权力式微,各国君主聚焦于扩充国家军力以自保或是图霸,根本无暇顾及礼乐。在屡屡碰壁的情势下,孔子自己也抱怨“莫我知也夫”。其实孔子如果愿意改变行事作风,趋附政治家的需求,或许就不必在周游列国的凄惶中被人取笑为“丧家之犬”。但他却不仅未曾放弃过对礼乐文化的坚守,还以一种积极乐观的态度周游列国,宣扬礼乐。在这种乐观情绪的感染下,他以一种坚忍的精神坚持着自己对理想的追求。“君子无终食之间违仁,造次必于是,颠沛必于是”,是他坚忍品格的最好宣言。即使厄于陈、蔡,他依然能够讲颂弦歌不衰,能够用“君子固穷,小人穷斯滥矣”的话来鼓励大家。

    孔子在充分吸收了西周礼乐文化的基础上,对日渐僵化的礼仪制度做了一番创造性的转化,适时提出“仁”的概念,希望人们可以从内心的真实情感出发,虔敬地践履礼的每一个仪节。他强调乐的重要性,乐教人听善音而动善情,听美乐而净化心灵,给人以无形的陶冶。在礼彰显皇权、划分等级的功能外,他将礼带出贵族范围,强调任何一个普通人,只要愿意学习礼乐,坚持德性的修养,皆有成为君子的可能。这种升华的礼的精神内涵和普遍意义,给了礼永恒的精神生命,使其不会仅仅只是一种制度,随着时代的更迭被遗忘在历史的角落里,而必然会在中国历史的长河中熠熠生辉,不可替代。

    对孔子来讲,遵守、提倡礼乐文化,不仅仅是为了保存这些细碎的礼仪细节,更在于其背后重要的意义——为了上下有序、社会安宁。“礼”的学说体系是孔子思想的核心,由礼治而达社会大同,是孔子的理想。孔子的伟大,就在于他改良的最终目的,并不是维护一家一姓的利益,他是怀着社会大同的情怀的。因此,具有合理性的思想,即便是在某一历史阶段因为“不合时宜”而遭受冷落甚至是贬抑,但时局一旦发生变革,仍可以“度尽劫波”而表现出旺盛的生命力。礼乐文化因为失去了宗法制度的社会土壤,在春秋战国时期因“不合时宜”而备受政治家们的冷落,在秦代又经历“焚书坑儒”的严厉打压,但终究“度尽劫波”,在汉以后的政治、社会生活中产生持续影响力,礼乐文化逐渐成为中华文化圈的标签,生活于其中的人“不学礼,无以立”。

(选自田家溧《孔子对礼乐文化的坚守与传承之路》,有删改)

同类题2

阅读理解

    The iPhone the iPad: each of Apple's products sounds cool and has become a fad(一时的风尚). Apple has cleverly taken advantage of the power of the letter “i”—and many other brands are following suit. The BBC's iPlayer—which allows Web users to watch TV programs on the Internet—used the title in 2008. A lovely bear—popular in the US and UK一that plays music and vide is called “iTeddy”. A slimmed-down version(简装本) of London's Independent newspaper was stated last week under the name “i”.

    In general, single-letter prefixes(前缀) have been popular since the 1990s, when terms such as e-mail and e-commerce first came into use.

    Most “i” products are targeted at young people and considering the major readers of Independent's “i”, it's no surprise that they've selected this fashionable name.

    But it's hard to see what's so special about the letter “i” Why not use “a”, “b”, or “c” instead? According to Tony Thorne, head of the Language Center at King's College, London, “i”works because its meaning has become ambiguous. When Apple uses “i”, no one knows whether it means Internet, information, individual or intcractive, Thorne told BBC Magazines. “Even when Apple created the iPod, it seems it didn't have one clear definition,” he says.

    “However, thanks to Apple, the term is now connected with portability.” adds Thorne.

    Clearly the letter “i” also agrees with the idea that the Western World is centered on the individual. Each person believes they have their own needs, and we love personalized products for this reason.

    Along with“Google” and “blog”, readers of BBC Magazines voted“i”as one of the top 20 words that have come to define the last decade.

    But as history shows, people grow tired of fads. From the 1900s to 1990s, products with “2000” in their names became fashionable as the year was connected with all things advanced and modern. How ever, as we entered the new century, the fashion disappeared.