BIMM118 Autonomic Nervous System. BIMM118 Autonomic Nervous System.
Autonomic Nervous System
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Transcript of Autonomic Nervous System
Autonomic Autonomic Nervous System
Dr. Sama-ul-Haque
ObjectivesObjectives Define autonomic nervous system.
Describe sympathetic and parasympathetic nervous system.
Enumerate the functions of sympathetic and parasympathetic nervous system.
ANS is the subdivision of the peripheral nervous ANS is the subdivision of the peripheral nervous system that regulates body activities that are generally system that regulates body activities that are generally not under conscious controlnot under conscious control
Visceral motorVisceral motor innervates innervates non-skeletalnon-skeletal ( (non-somatic) non-somatic) musclesmuscles
Composed of a special group of neurons serving: Composed of a special group of neurons serving: Cardiac muscle (the heart)Cardiac muscle (the heart) Smooth muscle (walls of viscera and blood vessels)Smooth muscle (walls of viscera and blood vessels) Internal organsInternal organs SkinSkin
The Autonomic Nervous System
Basic anatomical difference between the motor Basic anatomical difference between the motor pathways of the voluntary somatic nervous system (to pathways of the voluntary somatic nervous system (to skeletal muscles) and those of the autonomic nervous skeletal muscles) and those of the autonomic nervous systemsystem
Somatic division:Somatic division: Cell bodies of motor neurons reside in CNS (brain or spinal Cell bodies of motor neurons reside in CNS (brain or spinal
cord)cord) Their axons (as nerves) extend all the way to their skeletal Their axons (as nerves) extend all the way to their skeletal
muscles.muscles.
Autonomic system: chains of two motor neuronsAutonomic system: chains of two motor neurons 11stst = preganglionic neuron (in brain or cord) = preganglionic neuron (in brain or cord) 22ndnd = gangionic neuron (cell body in ganglion outside CNS) = gangionic neuron (cell body in ganglion outside CNS)
Axon of 1Axon of 1stst ( (preganglionicpreganglionic) neuron leaves ) neuron leaves CNS to synapse with the 2CNS to synapse with the 2ndnd ( (ganglionicganglionic) ) neuron.neuron.
Axon of 2Axon of 2ndnd ( (ganglionicganglionic) neuron extends to the ) neuron extends to the organ it servesorgan it serves
Diagram contrasts somatic (lower) and autonomic:
autonomic
somatic
this dorsal root ganglion is sensory
Divisions of the autonomic nervous systemDivisions of the autonomic nervous system
Parasympathetic divisionParasympathetic division Sympathetic divisionSympathetic division
Serve most of the same organs but cause Serve most of the same organs but cause opposing or antagonistic effectsopposing or antagonistic effects
Parasympathetic: routine maintenance“rest &digest”
Sympathetic: mobilization & increased metabolism “fight, flight or fright”
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Where they come fromWhere they come from
ParasympatheticCraniosacral
SympatheticThoracolumbar
T1 to L2
Paravertebral Paravertebral Ganglionic Ganglionic
chainchain or or
Sympathetic Sympathetic TrunkTrunk
Paravertebral Ganglionic
chain
Spinal NerveSpinal Nerve
Sympathetic nerveSympathetic nerve
Sympathetic Nervous system
Parasympathetic Nervous system
Functions of Sympathetic Nervous System Functions of Sympathetic Nervous System Increased Heart RateIncreased Heart Rate Increased Blood PressureIncreased Blood Pressure Pupil DilationPupil Dilation Decreased UrinationDecreased Urination Increased SweatingIncreased Sweating Bronchial DilationBronchial Dilation Decreased SalivationDecreased Salivation
Functions of Parasympathetic Nervous Functions of Parasympathetic Nervous System System
Decreased Heart RateDecreased Heart Rate Decreased Blood PressureDecreased Blood Pressure Pupil ConstrictionPupil Constriction Increased UrinationIncreased Urination Decreased SweatingDecreased Sweating Bronchial ConstrictionBronchial Constriction Increased SalivationIncreased Salivation
Thank You