某农科所通过如图育种过程培育成了高品质的糯小麦,相关叙述正确的是()() A.该育种

题型:单项选择题

问题:

某农科所通过如图育种过程培育成了高品质的糯小麦,相关叙述正确的是()(

A.该育种过程中运用的遗传学原理有基因重组、染色体数目变异

B.a过程能提高突变率,从而明显缩短了育种年限

C.a、c过程都需要对其萌发的种子用低温诱导或使用药物诱导

D.要获得yyRR,b育种过程的育种年限最短

考点:高中生物染色体变异与育种染色体变异与育种题库
题型:单项选择题

阅读下面的短文,在标有序号的空白处填入一个适当的词,或填入括号中所给单词的正确形式。

Language follows power. In an increasingly globalized world, some languages become the kings in terms of trade and communication. They jump geographic boundaries, pushing smaller languages toward    小题1: .

According to National Geographic magazine, one language dies every 14 days. By the next century nearly half of the roughly 7,000 languages spoken on Earth are   小题2:  to disappear as communities abandon native tongues in favor of English, Mandarin or Spanish.

This is    小题3:   Google.org is launching a new campaign called the Endangered Languages Project. It aims to digitally record the world’s little-known tongues and the heritages to which they are central.

What kind of languages are disappearing? Languages like Arogonese, which can be found in northern Spain, for example. Spoken by fewer than 10,000 people, this language seems to    小题4:   (disappear) within a few generations. Navajo and Ojibwa, both native to the Americans, are also close to extinction. Koro is the native language of a small population   小题5:  in the mountains of northeast India. It’s spoken by about 4,000 people.

The Endangered Languages website will record roughly 3,500 of the world’s little-spoken tongues. “  小题6:  every language that dies, humans are in danger of losing an enormous cultural heritage”, writes Loek Essers on the website Computerworld.com.

“As each one disappears, an understanding of how humans relate to the world around them, as well as scientific, medical, and botanical(植物的)knowledge, are all lost,    小题7:   is the expression of a community’s humor, love, and life.”

Users of the website can find    小题8:   which can be identified by their location on a map, or reached by means of a list that has been broken down into four categories: at risk, endangered, severely endangered, or unknown.    小题9:   can upload video or audio samples as well as share their knowledge of a language.

“Languages are alive and in constant change, and their extinction is not new,” write the site’s creators. “  小题10:   today we have the tools and technology that could become a game changer.”

题型:单项选择题

下列关于图中E线说法,正确的是:(  )

A.秦岭-淮河一线

B.800毫米等降水量线

C.400毫米等降水量线

D.第一、二阶梯分界线

题型:单项选择题

(四) 背景资料 A 安装公司承包某大楼空调设备监控系统的施工,主要监控设备有:现场控制器、电动调节阀、风阀驱动器、 温度传感器(铂电阻型)等。大楼的空调工程由B 安装公司施工。合同约定:全部监控设备由A 公司采购, 电动调节阀、风阀驱动器由B 公司安装,A 公司检查接线,最后由二家公司实施对空调系统的联动试运行调试。 A 公司项目部进场后,依据B 公司提供的空调工程施工方案、空调工程施工进度计划(见下表),设计单位 提供的空调机组监控方案(见下图),编制了监控系统施工方案,A 公司项目部在制定监控设备采购计划中, 采取集中采购、分批到货,使设备采购进度与施工进度合理搭接,在监控系统的施工过程中,A 公司及时与 B 公司协调,使监控系统施工进度符合空调工程的施工进度,监控系统和空调工程安装完成后,AB 公司进 行了空调系统的联动试运行调试,空调工程和监控系统按合同要求竣工。

 问题

A 公司项目部在实施监控系统施工进度计划过程中会受到哪些因素制约?(10 分)

题型:单项选择题

通过计时观察资料得知:人工挖二类土1m3的基本工作时间为6小时,辅助工作时间占工序作业时间的2%。准备与结束工作时间、不可避免的中断时间、休息时间分别占工作日的3%、2%、18%。则该人工挖二类土的时间定额是( )。

A.0.765工日/m3
B.0.994m3/工日
C.1.006工日/m3
D.1.307m3/工日

题型:单项选择题

股份有限公司发起人认购的股份,自公司成立之日起( )年内不得转让。

A.1
B.2
C.3
D.5

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