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.