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1、FirstEdition,2007ISBN9788189940829©Allrightsreserved.Publishedby:GlobalMedia1819,BhagirathPalace,ChandniChowk,Delhi-110006Email:globalmedia@dkpd.comTableofContents1.CirculatorySystem2.DigestiveSystem3.LymphaticSystemandImmunity4.NervousSystem5.Muscularan
2、dSkeletalSystems6.EndocrineSystem7.ReproductiveSystem8.IntegumentarySystemTHECIRCULATORYSYSTEMTypesofCirculatorySystemsVertebrateCardiovascularSystemVertebrateVascularSystemsTheHeartTheVascularSystemBloodTheLymphaticSystemLearningObjectivesTypesofCircula
3、torySystemsLivingthingsmustbecapableoftransportingnutrients,wastesandgasestoandfromcells.Single-celledorganismsusetheircellsurfaceasapointofexchangewiththeoutsideenvironment.Multicellularorganismshavedevelopedtransportandcirculatorysystemstodeliveroxygen
4、andfoodtocellsandremovecarbondioxideandmetabolicwastes.Spongesarethesimplestanimals,yeteventheyhaveatransportsystem.Seawateristhemediumoftransportandispropelledinandoutofthespongebyciliaryaction.Simpleanimals,suchasthehydraandplanaria,lackspecializedorga
5、nssuchasheartsandbloodvessels,insteadusingtheirskinasanexchangepointformaterials.This,however,limitsthesizeananimalcanattain.Tobecomelarger,theyneedspecializedorgansandorgansystems.Structuresthatservesomeofthefunctionsofthecirculatorysysteminanimalsthatl
6、ackthesystem.Multicellularanimalsdonothavemostoftheircellsincontactwiththeexternalenvironmentandsohavedevelopedcirculatorysystemstotransportnutrients,oxygen,carbondioxideandmetabolicwastes.Componentsofthecirculatorysysteminclude•blood:aconnectivetissueof
7、liquidplasmaandcells•heart:amuscularpumptomovetheblood•bloodvessels:arteries,capillariesandveinsthatdeliverbloodtoalltissuesThereareseveraltypesofcirculatorysystems.Theopencirculatorysystemiscommontomolluscsandarthropods.Opencirculatorysystems(evolvedini
8、nsects,mollusksandotherinvertebrates)pumpbloodintoahemocoelwiththeblooddiffusingbacktothecirculatorysystembetweencells.Bloodispumpedbyaheartintothebodycavities,wheretissuesaresurroundedbytheblood.Theresultingbloodflowisslu
