Nervous System (Anatomy) Updated 2026

Nervous System (Anatomy) Updated
2026
TwoMdivisionsMofMtheMNervousMSystemM-MAnswerM1.MCentralMnervousMsystemM(CNS)

2.MPeripheralMnervousMsystemM(PNS)



CentralMnervousMsystemM-MAnswerMConsistsMofMtheMbrainMandMspinalMcord



PeripheralMnervousMsystemM-MAnswerM-MconsistsMofMcranialMandMspinalMnerves

-MconnectsMCNSMtoMmuscles,Mglands,M&MallMsensoryMreceptors



NervousMTissueM-
MAnswerMControlsMandMintegratesMallMbodyMactivitiesMwithinMlimitsMthatMmaintainMlife



ThreeMbasicMfunctionsMofMnervousMtissueM-MAnswerM-
MSensingMchangesMwithMsensoryMreceptors

-MInterpretingMandMrememberingMthoseMchanges

-MreactingMtoMthoseMchangesMwithMeffectors

M*MmuscularMcontractions

M*MglandularMsecretions



SubdivisionsMofMtheMPNSM-MAnswerM-MSomaticM(voluntary)MnervousMsystemM(SNS)

-MAutonomic(involuntary)MnervousMsystem

-MEntericMnervousMsystemM(ENS)



SomaticMnervousMsystemM-MAnswerM-MneuronsMfromMreceptorsMtoMtheMCNS

-MmotorMneuronsMtoMskeletalMmuscleMtissue



AutonomicMnervousMsystemsM-MAnswerM-
MsensoryMneuronsMfromMvisceralMorgansMtoMCNS

-MmotorMneuronsMtoMsmoothMandMcardiacMmuscleMandMglands

M*MsympatheticMdivisionM(speedsMupMheartMrate)M-MmakesMpupilsMlarger

M*MparasympatheticMdivisionM(slowMdownMheartMrate)M-MmakesMpupils

, Msmaller



EntericMnervousMsystemM-MAnswerM-
MInvoluntaryMsensoryM&MmotorMneuronsMcontrolMGIMtract

-MneuronsMfunctionMindependentlyMofMANSM&MCNS



NeuronsM(nerveMcells)M-
MAnswerMTheMfunctionalMunitMofMtheMnervousMsystemMthatMhaveMelectricalMexcitability



CellMbodyM-MAnswerMSingleMnucleusMwithMprominentMnucleolus



CellMprocessesM-MAnswerMDendritesM&Maxons



PartsMofMaMneuronM-MAnswerM-MneuroglialMcells

-MnucleusMwithMnucleolus

-McellMbody

-MaxonsMorMdendrites



DendritesM-MAnswerM-MconductsMimpulsesMTOWARDSMtheMcellMbody

-MsurfacesMspecializedMforMcontactMwithMotherMneurons

(theMmoreMactivityMyouMdo,MtheMmoreMdendriteMbranchesMthatMgrow)



AxonsM-MAnswerM-MconductMimpulsesMAWAYMfromMcellMbody

-
MswollenMtipsMcalledMSYNAPTICMENDMBULBSMcontainMvesiclesMfilledMwithMneurotransmitt
ers

(AXONSM=MAWAY)



FunctionalMclassificationMofMneuronsM-MAnswerM-MSensoryM(afferent)Mneurons

M*MtransportMsensortMINFORMATIONMTOMCNSMmotorM(efferent)Mneurons

-MMotorM(efferent)Mneurons

M*MSendMmotorMnerveMimpulsesMtoMmusclesMandMglandsM(AWAYMFROMMCNS)