Scatteredthroughtheseasoftheworldarebillionsoftonsofsmallplantsandanimalscalledplankton.Mostoftheseplantsandanimalsaretoosmallforthehumaneyetosee.Theydriftaboutlazilywiththecurrents,providingabasicfoodformanylargeranimals.Planktonhasbeendescribedastheequivalentofthegrassesthatgrowonthedrylandcontinents,andthecomparisonisanappropriateone.Inpotentialfoodvaluehowever,planktonfaroutweighsthatofthelandgrasses.Onescientisthasestimatedthatwhilegrassesoftheworldproduceabout49billiontonsofvaluablecarbohydrateseachyear.Thesea’splanktongeneratesmorethantwiceasmuch.

Despiteitsenormousfoodpotential,littleeffortwasmadeuntilrecentlytofarmplanktonaswefarmgrassesonland.Nowmarinescientistshaveatlastbeguntostudythispossibility,especiallyasthesea’sresourcesloomevenmoreimportantasameansoffeedinganexpandingworldpopulation.

Nooneyethasseriouslysuggestedthat“planktonburgers”maysoonbecomepopulararoundtheworld.Asapossiblefarmedsupplementaryfoodsource,however,planktonisgainingconsiderableinterestamongmarinescientists.

Onetypeofplanktonthatseemstohavegreatharvestpossibilitiesisatinyshrimplikecreaturecalledkrill.Growingtotwoorthreeincheslong,krillprovidethemajorfoodforthegiantbluewhale,thelargestanimalevertoinhabittheEarth.Realizingthatthiswhalemaygrow100feetandweigh150tonsatmaturity,itisnotsurprisingthateachonedevoursmorethanonetonofkrilldaily.

Krillswimaboutjustbelowthesurfaceinhugeschoolssometimesmileswide,mainlyinthecoldAntarctic.Becauseoftheirpinkcolor,theyoftenappearasasolidreddishmasswhenviewedfromashiporfromtheair.Krillareveryhighinfoodvalue.Apoundofthesecrustaceanscontainsabout460calories—aboutthesameasshrimporlobster,towhichtheyarerelated.

Ifthekrillcanfeedsuchhugecreaturesaswhales,manyscientistsreason,theymustcertainlybecontendersasnewfoodsourceforhumans.

1.Whichofthefollowingbestportraystheorganizationofthepassage?

A.Theauthorpresentstheadvantagesanddisadvantagesofplanktonasafoodsource.

B.Theauthorquotespublicopiniontosupporttheargumentforfarmingplankton.

C.Theauthorclassifiesthedifferentfoodsourcesaccordingtoamountofcarbohydrate.

D.Theauthormakesageneralstatementaboutplanktonasafoodsourceandthenmovestoaspecificexample.

2.Accordingtothepassage,whyisplanktonregardedtobemorevaluablethanlandgrasses?

A.Itiseasiertocultivate.

B.Itproducesmorecarbohydrates.

C.Itdoesnotrequiresoil.

D.Itismorepalatable.

3.Whydoestheauthormention“planktonburgers”?

A.Todescribetheappearanceofonetypeofplankton.

B.Toillustratehowmuchplanktonawhaleconsumes.

C.Tosuggestplanktonasapossiblefoodsources.

D.Tocomparethefoodvaluesofbeefandplankton.

4.Whatismentionedasoneconspicuousfeatureofkrill?

A.Theyarethesmallestmarineanimals.

B.Theyarepinkincolor.

C.Theyaresimilarinsizetolobsters.

D.Theyhavegrasslikebodies.

5.Theauthormentionsallofthefollowingasreasonswhyplanktoncouldbeconsideredahumanfoodsourceexceptthatitis___.

A.highinfoodvalue.

B.inabundantsupplyintheoceans.

C.anappropriatefoodforotheranimals.

D.freeofchemicalsandpollutants.

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Passage3

Questions11to15arebasedonthefollowingpassage:

UnliketheirAmericanorEuropeancounterparts,carsalesmeninJapanworkhardtogetabuyer.Insteadoflyinglazilyaroundshowroomswaitingforcustomerstodropby,manyJapanesecarsalesmenstillgoouttogetthem.Theywalkwearilyalongthestreetscarsdoor-to-door.Newcustomersarehuntedwithfruitandcakesontheirbirthdays.Butlifeisgettingtough,andnotjustbecausenew-carsalesarefalling.

WithmoreJapanesewomen(whooftencontrolthehouseholdbudget)goingouttowork,thesalesmenincreasinglyfindnobodyathomewhentheycall.Thatmeansanothervisitintheeveningortheweekend.Thentheyfaceanextraproblem:morepeople,especiallytheyoung,prefertochooseanewcarfromashowroomwheretheycancomparedifferentmodels.

Evenaslateasthemid-1980ssome90%ofnewcarsweresolddoor-to-door.Insomeruralareasmostnewcarsarestillsoldthisway.Butinthebigcitiesmorethanhalfthenewcarsarenowsoldfromshowrooms.

AlthoughinvestinginshowroomsisexpensivebecauseofthehighcostofJapaneseland,dealershavelittlechoice.AlaborshortageandhigheramongJapan’sworkforcearemakingitdifficulttohiredoor-to-doorsalesmen.MostofaJapanesecarsalesman’sworkingdayisspentdoingfavorsforcustomers,likearranginginsuranceorpickingupvehiclesforservicing,ratherthanactuallyselling.

Japan’sdoorstepcarsalesmenarenotabouttovanish.Thepersonalservicetheyprovideissodeep-rootedinJapanthattheyarelikelytooperatealongsidetheglitteringnewshowrooms.Thetwosystemsevencomplementeachother.Whatincreasinglyhappensisthattheshowroomattractstheinterestofapotentialbuyer,givingthefootsoresalesmenafirmleadtofollowupwithahomevisit.

11.Japanesecarsalesusuallydonotwaitatshowroomsforcustomerstodropby;instead,.

A.theysellcarsdoor-to-door

B.theybuypresentsfortheircustomers

C.theyenjoythemselvesinrecreationcenters

D.theygoouttodomarketresearches

12.Impliedbutstated:thecompetitionincarmarketis.

A.lightB.moderateC.fierceD.unfair

13.Youngpeopleliketobuyanewcar.

A.athomeB.fromashowroom

C.madeintheU.S.A.D.madeinJapan

14.ThesquadronofJapanesecarsalesmenisreducingbecauseof.

A.alaborshortage

B.higherexpectationsamongJapan’sworkforce

C.highcostland

D.bothAandB

15.Japanesecarsalesmentotheircustomersmanyfavorssuchas.

A.showingthemaroundinanexhibition

B.arranginginsurance

C.payingthemavisitonweekends

D.sellingolecarsforthem

PartIVTranslation

Thecaptainrealizedthatthementriedtodeceivehimsohemadethemworkveryhardfortherestofthevoyage.(PassageOne)

Theauthortellsusinparagraph4________.

A、thereasonsforkeepingmedicinesathome
B、people'sdoubtabouttakingdrugs
C、whatkindofmedicinepeopleshouldprepareathome
D、thepossibleharmsself-medicationmaydotopeople

Advertisementsareaimedatpeoplesufferingfrommildcomplaintsbecause________.

A、theyoftenwatchadsonTV
B、theyaremorelikelytobuythedrugsadvertised
C、theygenerallyleadasedentarylife
D、theydon'ttaketosportsandeasilycatchcolds

Withoutregularsuppliesofsomehormonesourcapacitytobehavewouldbeseriouslyimpaired;withoutotherswewouldsoondie.Tinyamountsofsomehormonescanmodifymoodsandactions,ourinclinationtoeatordrink,ouraggressivenessorsubmissiveness,andourreproductiveandparentalbehavior.Andhormonesdomorethaninfluenceadultbehavior;earlyinlifetheyhelptodeterminethedevelopmentofbodilyformandmayevendetermineanindividual’sbehavioralcapacities.Laterinlifethechangingoutputsofsomeendocrineglandsandthebody’schangingsensitivitytosomehormonesareessentialaspectsofthephenomenaofaging.

Communicationwithinthebodyandtheconsequentintegrationofbehaviorwereconsideredtheexclusiveprovinceofthenervoussystemuptothebeginningofthepresentcentury.TheemergenceofendocrinologyasaseparatedisciplinecanprobablybetracedtotheexperimentsofBaylissandStarlingonthehormonesecretion.Thissubstanceissecretedfromcellsintheintestinalwallswhenfoodentersthestomach;ittravelsthroughthebloodstreamandstimulatesthepancreastoliberatepancreaticjuice,whichaidsindigestion.Byshowingthatspecialcellssecretchemicalagentsthatareconveyedbythebloodstreamandregulatedistanttargetorgansortissues.Baylissandstarlingdemonstratedthatchemicalintegrationcouldoccurwithoutparticipationofthenervoussystem.

Theterm“hormone”wasfirstusedwithreferencetosecretion.StarlingderivedthetermfromtheGreekhormone,meaning“toexciteorsetinmotion.Theterm“endocrine”wasintroducedshortlythereafter“Endocrine”isusedtorefertoglandsthatsecretproductsintothebloodstream.Theterm“endocrine”contrastswith“exocrine”,whichisappliedtoglandsthatsecrettheirproductsthoughductstothesiteofaction.Examplesofexocrineglandsarethetearglands,thesweatglands,andthepancreas,whichsecretspancreaticjuicethroughaductintotheintestine.Exocrineglandsarealsocalledductglands,whileendocrineglandsarecalledductless.

1.Whatistheauthor’smainpurposeinthepassage?

A.Toexplainthespecificfunctionsofvarioushormones.

B.Toprovidegeneralinformationabouthormones.

C.Toexplainhowtheterm“hormone”evolved.

D.Toreportonexperimentsinendocrinology.

2.Thepassagesupportswhichofthefollowingconclusions?

A.Thehumanbodyrequireslargeamountsofmosthormones.

B.Synthetichormonescanreplaceaperson’snaturalsupplyofhormonesifnecessary.

C.Thequantityofhormonesproducedandtheireffectsonthebodyarerelatedtoaperson’sage.

D.Theshortchildoftallparentsverylikelyhadahormonedeficiencyearlyinlife.

3.ItcanbeinferredfromthepassagethatbeforetheBaylissandStarlingexperiments,mostpeoplebelievedthatchemicalintegrationoccurredonly___.

A.duringsleep.

B.intheendocrineglands.

C.undercontrolofthenervoussystem.

D.duringstrenuousexercise.

4.Theword“liberate”couldbestbereplacedbywhichofthefollowing?

A.EmancipateB.DischargeC.SurrenderD.Save

5.Accordingtothepassageanothertermforexocrineglandsis___.

A.ductglands

B.endocrineglands

C.ductlessglands

D.intestinalglands.

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