首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
About fifty years ago, plant physiologists set out to grow roots by themselves in solutions in laboratory flasks. The scientists
About fifty years ago, plant physiologists set out to grow roots by themselves in solutions in laboratory flasks. The scientists
admin
2013-11-07
50
问题
About fifty years ago, plant physiologists set out to grow roots by
themselves
in solutions in laboratory flasks. The scientists found that the nutrition of isolated roots was quite simple. They required sugar and the usual minerals and vitamins. However, they did not require organic nitrogen compounds. These roots got along fine on mineral inorganic nitrogen. Roots are capable of making their own proteins and other organic compounds. These activities by roots require energy, of course. The process of respiration uses sugar to make the high energy compound ATP, which drives the biochemical reactions. Respiration also requires oxygen. Highly active roots require a good deal of oxygen.
The study of isolated roots has provided an understanding of the relationship between shoots and roots in
intact
plants. The leaves of the shoots provide the roots with sugar and vitamins, and the roots provide the shoots with water and minerals. In addition, roots can provide the shoots with organic nitrogen compounds. This
conies in handy
for the growth of buds in the early spring when leaves are not yet functioning. Once leaves begin photosynthesizing, they produce protein, but only mature leaves can "export" protein to the rest of the plant in the form of amino acids.
The underlined word "themselves" in Paragraph 1 refers to______.
选项
A、plant physiologists
B、solutions
C、laboratory flasks
D、roots
答案
A
解析
细节题型。见第一段第一句:About fifty years ago,plant physiologists set out to growroots by t—hems—elves in solutions in laboratory flasks.这里指plant physiologists自己培育根用作物;因此themselves在此应为正确选项。
转载请注明原文地址:https://www.kaotiyun.com/show/YIwO777K
本试题收录于:
CATTI三级笔译综合能力题库翻译专业资格(CATTI)分类
0
CATTI三级笔译综合能力
翻译专业资格(CATTI)
相关试题推荐
SOILQUALITY1Soilisarenewableresource,butonlyonaverylongtimescale,asittakeshundredsorthousandsofyearsfo
NarratorListentoatalkbetweentwostudents.Nowgetreadytoanswerthequestions.Youmayuseyournotestohelp
Manypeoplehavelearnedaforeignlanguageintheirowncountry;othershavelearnedaforeignlanguageinthecountryinwhich
ThissectionmeasuresyourabilitytounderstandacademicpassagesinEnglish.TheReadingsectionofTOEFLiBTisdividedinto
Whatdidtheprofessornotcoverthatsheoriginallyintendedto?
A、Herhometowndoctorworksatthestudenthealthcenter.B、Shecannothelpthemanchooseadoctor.C、Shedidn’tknowsheneeded
GeologyWhatistheprofessor’spurposeintellingthestudentsaboutmovingrocks?
Accordingtotheprofessor,whatassumptionmightareductionistmakewhenanalyzingantcolonies?
Marketingis______justdistributinggoodsfromthemanufacturertothefinalcustomer.
______theEnglishexamination,IwouldhavegonetotheconcertlastSunday.
随机试题
具有止血作用的药物是()(2009年第142题)
独立学校(英国)
幂级数(x+1)n的收敛区间为()
诊断PNH最基本的试验是
体现有利原则的是体现公正原则的是
中小企业是我国最具活力的企业群体,在GDP中的比重约占60%,提供了70%的城镇就业岗位。自2011年以来,受需求不足、成本上升等不利因素的影响,中小企业的发展面临较大困难,为此国家加大了对中小企业的扶持力度,这有利于()。
()是对内调控的技能,它所涉及的概念和规则反映人类自身认识活动的规律,无法从外部直接观察到,这类概念和规则难以通过直观演示的方法交给学生。
(01年)设f(χ)的导数在χ=a处连续,又=-1,则
设A为3阶矩阵,E为3阶单位矩阵,α,β是线性无关的3维列向量,且A的秩r(A)=2,Aα=β,Aβ=α,则|A+3E|为()
在考生文件夹下,完成如下操作:1.打开考生文件夹下的表单one,如下图所示,编写“显示”命令按钮的Click事件代码,使表单运行时单击该命令按钮则在Text1文本框中显示当前系统日期的年份(提示:通过设置文本框的Value属性实现,系统日期函数是
最新回复
(
0
)