[考试宝典]2011职称英语理工ab级阅读理解精讲

[考试宝典]2011职称英语理工ab级阅读理解精讲

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时间:2018-08-30

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1、职称英语考试宝典系列软件职称英语理工AB级阅读理解精讲(1) WhereHaveAlltheBeesGone?  Scientistswhostudyinsectshavearealmysteryontheirhands.Allacrossthecountry,honeybeesareleavingtheirhivesandneverreturning.Researcherscallthisphenomenoncolony-collapse1disorder.Accordingtosurveysofb

2、eekeepersacrossthecountry,25to40percentofthehoneybeesintheUnitedStateshavevanishedfromtheirhivessincelastfall.Sofar,noonecanexplainwhy.  Colonycollapseisaseriousconcernbecausebeesplayanimportantroleintheproductionofaboutone-thirdofthefoodsweeat.Astheyfe

3、ed,honeybeesspreadpollenfromflowertoflower.Withoutthisprocess,aplantcan’tproduceseedsorfruits.  Now,agroupofscientistsandbeekeepershaveteameduptotrytofigureoutwhat’scausingthealarmingcollapseofsomanycolonies.Bysharingtheirexpertiseinhoneybeebehavior,hea

4、lth,andnutrition,teammembershopetofindoutwhat’scontributingtothedeclineandtopreventbeedisappearancesinthefuture.  Itcouldbethatdiseaseiscausingthedisappearanceofthebees.Toexplorethatpossibility,JayEvans,aresearcherattheUnitedStatesDepartmentofAgricultur

5、e(USDA)BeeResearchLaboratory2,examinesbeestakenfromcoloniesthatarecollapsing.“Weknowwhatshealthybeeshouldlooklikeontheinside,andwecanlookforphysicalsignsofdisease,”hesays.Andbeesfromcollapsingcoloniesdon’tlookveryhealthy.“Theirstomachsareworndown,compar

6、edtothestomachsofhealthybees,”Evanssays.Itmaybethataparasiteisdamagingthebees’digestiveorgans.Theirimmunesystemsmaynotbeworkingastheyshould.Moreover,theyhavehighlevelsofbacteriainsidetheirbodies.  Anothercauseofcolony-collapsedisordermaybecertainchemica

7、lsthatfarmersapplytokillunwantedinsectsoncrops,saysJerryHayes,chiefbeeinspectorfortheFloridaDepartmentofAgriculture3.Somestudies,hesays,suggestthatacertaintypeofinsecticideaffectsthehoneybee’snervoussystem(whichincludesthebrain)andmemory.“Itseemslikehon

8、eybeesaregoingoutandgettingconfusedaboutwheretogoandwhattodo,”hesays.  Ifitturnsoutthatadiseaseiscontributingtocolonycollapse,bees’genescouldexplainwhysomecolonieshavecollapsedandothershavenot.Inanygroupofbeestherearemanydifferen

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