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
69
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.
【C17】
选项
A、discover
B、look for
C、uncover
D、search for
答案
C
解析
意思为揭示出。
转载请注明原文地址:https://www.kaotiyun.com/show/42LK777K
0
专业英语四级
相关试题推荐
IseethisprincipalalloverasIgothroughmyday.Iseerimsoncarwheelsthatcostupwardsof$500,justforalittlebit
Ofthefourgroupsofstudents,whoscoredthelowestinmathsaccordingtothesurvey?
Ofthefourgroupsofstudents,whoscoredthelowestinmathsaccordingtothesurvey?
SARS,whichhadaffectedmillionsofpeoplethroughouttheworld,______doctorsandpublichealthworkersatfirst.
Thebackgardenofourhousecontainsalawn,______verypleasanttositoninsummer.
Thedesegregationwasachievedthroughanumberofstruggles,_____havebeenmentionedinpreviouschapters.
______peoplewerekilledduringtheaircrash.
Oneoftheaimsofteachingscienceis,throughlearning,toenablestudentstodevelopacompletepersonalitybycreativity,ho
Oneoftheaimsofteachingscienceis,throughlearning,toenablestudentstodevelopacompletepersonalitybycreativity,ho
随机试题
A、producesmuchmoreglobalwarmingthanacarbon-dioxideforcingofthesamemagnitudeB、contributedto25percentofobserved
下述哪些属死胎的声像图表现
四环素的抗菌谱中不包括
从意识主体的角度,法律意识可以分()。
消费者购买房地产后主要用来出租以获得回报,这种对房地产的需求称为()。
估价人员如果与估价对象有利益关系或与委托人等有关当事人有利害关系,应当回避。()
以下关于劳动法的监督检查制度的说法,不正确的是()。
如图所示,AD是∠FAB的角平分线,延长AF与⊙O的切线CD交于C,AB是⊙O的直径.若DE⊥AB,证明:AE·BE=AC·CF.
请简述使用PHP进行MySQL数据库编程的基本步骤。
ThisyearthecombinedadvertisingrevenuesofGoogleandYahoo!willrivalthecombinedprimetimeadrevenuesofAmerica’sthre
最新回复
(
0
)