Autonomic Nervous System PDF

Autonomic nervous system Structure and origin : AFFERENTNEURONS *CARRYSENSORYINFOfromRECEPTORSinSKIN/ OTHERORGANS→CENTRALNERVOUSSYSTEM ~akaSENSORYNEURONS...

Autonomic nervous system Structure and origin : AFFERENTNEURONS *CARRYSENSORYINFOfromRECEPTORSinSKIN/ OTHERORGANS→CENTRALNERVOUSSYSTEM ~akaSENSORYNEURONS *CELLBODIESareLOCATEDOUTSIDEofthe SPINALCORD SKIN DORSALROOT AUTONOMICDIVISION DORSALROOT GANGLION *REGULATESINVOLUNTARY BODYRESPONSES SPINAL CORD VENTRALROOT BLOOD VESSELS SOMATICDIVISION *VOLUNTARYMOVEMENTby SKELETALMUSCLES EFFERENTNEURONS *CARRYMOTORINFOfromBRAIN→PERIPHERAL NERVOUSSYSTEM ~akaMOTORNEURONS *CELLBODIESareLOCATEDintheVENTRAL SKELETAL HORNoftheSPINALCORD MUSCLES OSMOSIS.org Autonomic nervous system Autonomic nervous system Autonomic nervous system Somatic nervous system Control Involuntary Voluntary Type 2 types One Efferent 2 efferent One Muscle Smooth muscle – cardiac Skeletal muscle muscle Chemical transmitter Acetylcholine Acetylcholine Norepinephrine Autonomic ganglia Present Absent Arise from LHC AHC  Autonomic nervous system Autonomic ganglia :  Autonomic nervous system Autonomic ganglia : Definition: collection of neurons outside CNS Function: acts as distributing center Types: 1. paravertebral ganglia ( lateral ) 2. collateral ganglia 3. terminal ganglia  Autonomic nervous system paravertebral ganglia ( lateral ) present on both sides of vertebral column relay of sympathetic nervous system  Autonomic nervous system collateral ganglia : present midway between spinal cord and viscera. relay of sympathetic. relay of parasympathetic. terminal ganglia : present near or inside the viscous. relay of parasympathetic.  Divisions of Autonomic nervous system 1. Sympathetic nervous system. 2. Parasympathetic nervous system.  Divisions of Autonomic nervous system 1. Sympathetic nervous system.  Divisions of Autonomic nervous system 2. Parasympathetic nervous system.  Sympathetic nervous system Origin : thoracolumbar (LHC of all thoracic and upper 3 lumbar segments)  Functions of sympathetic nervous system On head and neck : 1. Eye: pupil dilatation ( mydriasis ) due to contraction of dilator pupillae muscle elevation of upper eyelid ( widening of palpebral fissure ) decrease tear secretion of lacrimal gland 2. Salivary glands: Decreases salivary secretions  Functions of sympathetic nervous system On thorax : ( heart and lung ) Heart: increase excitability and rate of conduction +ve inotropic effect ( increase in force of contraction ) +ve chronotropic effect ( increase in heart rate ) vasodilatation of coronary vessels  Functions of sympathetic nervous system On thorax : ( heart and lung ) Lung: bronchodilatation ( relaxation of bronchial muscles ). vasoconstriction of pulmonary vessels.