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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.
Passage2
Questions6to10arebasedonthefollowingpassage:
Thefoodweeatseemstohaveprofoundeffectsonourhealth.Althoughsciencehasmadeenormousstepsinmakingfoodmorefittoeat,ithas,atthesametime,mademanyfoodsunfittoeat.Someresearchhasshowntat40percentofcancerisrelatedtothedietaswell,especiallycancerofthecolon.Differentculturesatemorepronetogetcertainillnessesbecauseofthefoodthatischaracteristicinthesecultures.Thatfoodisrelatedtoillnessisnotanewdiscovery.In1945,governmentresearchersrealizedthatnitratesandnitrites,commonlyusedtopreservecolorinmeats,andotherfoodadditives,causedcancer.Yetthesecarcinogenicadditivesremaininourfood,anditbecomesmoredifficultallthetimetoknowwhichthingsonthepackaginglabelsofprocessedfoodarehelpfulorharmful.Theadditivesthatweeatarenotallsodirect.Farmersoftengivepenicillintobeefandpoultry,andbecauseofthis,penicillinhasbeenfoundinthemilkoftreatedcows.Sometimessimilardrugsareadministeredtoanimalsnotformedicinalpurposes,butforfinancialreasons.Thefarmersaresimplytryingtofattentheanimalsinordertoobtainahigherpriceonthemarket.AlthoughtheFoodandDrugAdministration(FDA)hastriedrepeatedlytocontroltheseprocedures,thepracticescontinue.
6.Howhassciencedoneadisservicetomankind?
A.Becauseofscience,mostofthefoodsweeattodayarecontaminated.
B.Ithascausedalackofinformationconcerningthevalueoffood.
C.Asaresultofscientificintervention,somepotentiallyharmfulsubstanceshasbeenaddedtoourfood.
D.Thescientistshavepreservedthecolorofmeats,butnotofvegetables.
7.Whatarenitratesusedfor?
A.Theypreservesflavorinpackagedfoods.
B.Theypreservethecolorofmeats.
C.Theyaretheobjectsofresearch.
D.Theycausetheanimalstobecomefatter.
8.TheFDAhastriedrepeatedlytocontrol.
A.theattempttofattentheanimals
B.theattempttocuresickanimals
C.theusingofdrugstoanimals
D.theusingofadditivestopreservethedoloroffood
9.Theword“carcinogenic”meansmostnearlythesameas.
A.trouble-makingB.color-retaining
C.money-savingD.cancer-causing
10.WhichofthefollowingstatementsisNOTtrue?
A.Drugsarealwaysgiventoanimalsformedicalreasons.
B.Someoftheadditivesinourfoodareaddedtothefooditselfandsomearegiventothelivinganimals.
C.Researchershaveknownaboutthepotentialhazardsofthefoodadditivesforoverthirty-fiveyears.
D.Foodmaycausefortypercentofcancerintheworld.
