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
Trees do more than make life pleasant; they make life【C1】______ . Trees get【C2】______ through their roots and, primarily through
Trees do more than make life pleasant; they make life【C1】______ . Trees get【C2】______ through their roots and, primarily through
admin
2013-08-03
61
问题
Trees do more than make life pleasant; they make life【C1】______ . Trees get【C2】______ through their roots and, primarily through their leaves, they 【C3】______ carbon dioxide【C4】______ the air. Then, with the action of sunlight on cells 【C5】 chlorophyll and other materials, chemical reactions 【C6】______ , and oxygen is 【C7】______ . Through photosynthesis, an acre of trees produces enough oxygen to sustain three 【C8】______ .
Eating wood might seem odd,【C9】______ many low calorie breads and other baked goods now include powdered cellulose【C10】______ acts as a bulking agent to help hold the foods together.
Trees have always been green machines,【C11】______ substances that humans【C12】______ to use. The ancient Greeks, for example, treated pain【C13】______ a tea made by boiling willow leaves and bark; a tea modern scientists now know contains silicon, a precursor of acetylsalicylic acid aspirin. For centuries, the Chinese have【C14】______ medicines from the ginkgo tree. More recently, researchers isolated and synthesized the chemical ginkgolide from the tree【C15】______ use in treating asthma, toxic shock and other ills.
【C16】______ scientists unlock the secrets of trees, they 【C17】______ surprising facts. In the early 1980s David Rhoades, a chemical【C18】______ at the University of Washington, Seattle, discovered that trees send unseen signals to each other. When willows are attacked by webworms and tent caterpillars, they【C19】______ a chemical that alerts nearby willows. The neighboring trees respond by pumping more tannin into their leaves, making them more【C20】______ for the insects to digest.
【C16】
选项
A、Where
B、Then
C、Until
D、As
答案
D
解析
as= when。
转载请注明原文地址:https://www.kaotiyun.com/show/Z2LK777K
0
专业英语四级
相关试题推荐
IseethisprincipalalloverasIgothroughmyday.Iseerimsoncarwheelsthatcostupwardsof$500,justforalittlebit
Ofthefourgroupsofstudents,whoscoredthelowestinmathsaccordingtothesurvey?
______ingovernmentwasexposedthroughtheagencyofthepress.
Moreover,inthemodernage______humanbeingsdependsomuchonmachines,FrancisChichesterhadgivenmenthroughouttheworl
Thehouseallocatedtothemwaspleasantand______.
Howmanypolicemenwerekilledinthebombing?
Hemighthavebeenkilled______thetimelyarrivaloftheambulance.
Howmanypeoplewerekilledinthemassacre?
随机试题
使用一次后即失去效能的消耗性物品是()
有关不协调性宫缩乏力,不正确的是()
下列税率中,不属于企业所得税税率的是()。
浙江浙海服装进出口公司(3313910194)在对口合同项下进口蓝湿牛皮(法定计量单位:千克),由浙江嘉宁皮革有限公司(3313920237)加工成牛皮沙发革。承运船舶在帕腊纳瓜港装货启运,泊停釜山港转“HANSASTAVANGER”号轮(航次号HV30
()情况下,借款人的营运能力较好。
______是指借款企业由于财务状况恶化或其他原因而出现的还款困难,银行在充分评价贷款风险并与贷款企业协商的基础上,修改或重新制定贷款偿还方案,调整贷款合同条款,控制和化解贷款风险的行为。
大众旅游时期的导游服务主要呈现()特征。
Emergingfromthe1980censusisthepictureofanationdevelopingmoreandmoreregionalcompetition,aspopulationgrowthin
Everyoneknowsthattoomuchtimeinthesuncanexposeyoutoexcessiveultravioletradiation,whichcanleadtoskincancers.【
TheancientreputationofVikingsasbloodthirstyraidersoncoldnorthernseashasundergonearadicalchangeinrecentdecades
最新回复
(
0
)