当前位置:考试网  > 试卷库  > 技能鉴定  > 特种作业  > 危险化学品安全作业  > 过氧化工艺作业  > 安全发展的基本任务是()
试题预览

安全发展的基本任务是()

更新时间:2024-11-16 04:26:01
A、保障人民群众的生命财产安全
B、促进经济发展
C、减少事故发生
收藏
纠错
正确答案:

A

答案解析:

暂无解析

你可能感兴趣的试题

Hewasluredintoacrimehewouldnot____________havecommitted.

Heresented_____towait.Heexpectedtheminister_____himatonce.

汉译英:手机改变了人与人之间的关系。通常有注意到会议室的门上的告示,写着―关闭手机。‖然而,会议室仍然充满着铃声。我们都是普通人,没有很多重要的事情。但是,我们也不愿轻易关闭手机。打开手机象征着我们与世界的联系。手机反映出我们的社交饥渴。我们经常看到,一个人走着走着,就突然停下来了,眼睛盯着他的手机,不管他在那里,无论是在道路中心或旁边有厕所。

_____atinthisway,thepresenteconomicsituationdoesn'tseemsogloomy.

AsGilbertWhite,Darwin,andothersobservedlongago,allspeciesappeartohavetheinnatecapacitytoincreasetheirnumbersfromgenerationtogeneration.Thetaskforecologistsistountangletheenvironmentaandbiologicalfactorsthatholdthisintrinsiccapacityforpopulationgrowthincheckoverthelongrun.Thegreatvarietyofdynamicbehaviorsexhibitedbydifferentpopulationmakesthistaskmoredifficult:sompopulationsremainroughlyconstantfromyeartoyear;othersexhibitregularcyclesofabundanceandscarcity;stillothersvarywildly,withoutbreaksandcrashesthatareinsomecasesplainlycorrelatedwiththeweather,andinothercasesnot.Toimposesomeorderonthiskaleidoscopeofpatterns,oneschoolofthoughtproposesdividingpopulationsintotwogroups.Theseecologistspositthattherelativelysteadypopulationshavedensity-dependentgrowthparameters;thatis,ratesofbirth,death,andmigrationwhichdependstronglyonpopulationdensity.Thehighlyvaryingpopulationshavedensity-independentgrowthparameters,withvitalratesbuffetedbyenvironmentalevents;theseratesfluctuateinawaythatiswhollyindependentofpopulationdensity.Thisdichotomyhasitsuses,butitcancauseproblemsiftakentooliterally.Foronething,nopopulationcanbedrivenentirelybydensity-independentfactorsallthetime.Nomatterhowseverelyorunpredictablybirth,death,andmigrationratesmaybefluctuatingaroundtheirlong-termaverages,iftherewerenodensity-dependenteffects,thepopulationwould,inthelongrun,eitherincreaseordecreasewithoutbound(barringamiraclebywhichgainsandlossescanceledexactly)。Putanotherway,itmaybethatonaverage99percentofalldeathsinapopulationarisefromdensity-independentcauses,andonlyonepercentfromfactorsvaryingwithdensity.Thefactorsmakinguptheonepercentmayseemunimportant,andtheircausemaybecorrespondinglyhardtodetermine.Yet,whetherrecognizedornot,theywillusuallydeterminethelong-termaveragepopulationdensity.Inordertounderstandthenatureoftheecologist’sinvestigation,wemaythinkofthedensity-dependenteffectsongrowthparametersasthesignalecologistsaretryingtoisolateandinterpret,onethattendstomakethepopulationincreasefromrelativelylowvaluesordecreasefromrelativelyhighones,whilethedensity-independenteffectsacttoproducenoiseinthepopulationdynamics.Forpopulationsthatremainrelativelyconstant,orthatoscillatearoundrepeatedcycles,thesignalcanbefairlyeasilycharacterizedanditseffectsdescribed,eventhoughthecausativebiologicalmechanismmayremainunknown.Forirregularlyfluctuatingpopulations,wearelikelytohavetoofewobservationstohaveanyhopeofextractingthesignalfromtheoverwhelmingnoise.Butitnowseemsclearthatallpopulationsareregulatedbyamixtureofdensity-dependentanddensity-independenteffectsinvaryingproportions.

1.Theauthorofthetextisprimarilyconcernedwith

[A]Discussingtwocategoriesoffactorsthatcontrolpopulationgrowthandassessingtheirrelativeimportance.

[B]Describinghowgrowthratesinnaturalpopulationsfluctuateovertimeandexplainingwhythesechangesoccur.

[C]Proposingahypothesisconcerningpopulationsizeandsuggestingwaystotestit.

[D]Posingafundamentalquestionaboutenvironmentalfactorsinpopulationgrowthandpresentingsomecurrentlyacceptedanswer.

2.Itcanbeinferredfromthetextthattheauthorconsidersthedichotomydiscussedtobe

[A]Applicableonlytoerraticallyfluctuatingpopulations.

[B]instrumental,butonlyifitslimitationsarerecognized.

[C]Dangerouslymisleadinginmostcircumstances.

[D]Acompleteandsufficientwaytoaccountforobservedphenomena.

3.tothetext,allofthefollowingbehaviorshavebeenexhibitedbydifferentpopulationsEXCEPT

[A]Roughlyconstantpopulationlevelsfromyeartoyear.

[B]Regularcyclesofincreasesanddecreasesinnumbers.

[C]Erraticincreasesinnumberscorrelatedwiththeweather.

[D]Uncheckedincreasesinnumbersovermanygenerations.

4.Thediscussionconcerningpopulationinthethirdparagraphservesprimarilyto

[A]Demonstratethedifficultiesecologistsfaceinstudyingdensity-dependentfactorslimitingpopulationgrowth.

[B]Advocatemorerigorousstudyofdensity-dependentfactorsinpopulationgrowth.

[C]Provethatthedeathratesofanypopulationareneverentirelydensity-independent.

[D]underlinetheimportanceofevensmalldensity-dependentfactorsinregulatinglong-termpopulationdensities.

5.Inthetext,theauthordoesallofthefollowingEXCEPT

[A]Citetheviewsofotherbiologists.

[B]Defineabasicproblemthatthetextaddresses.

[C]Presentconceptualcategoriesusedbyotherbiologists.

[D]Describetheresultsofaparticularstudy.