Hirsch - Visceral Motor Flashcards
somatic vs, visceral
voluntary vs. involuntary(autonomic)
- somatic: motor neurons in CNS, very precise connections with targets
- visceral: motor/effector neurons in PNS, diffuse connections
two main subdivisions in visceral nervous system
*sympathetic and parasympathetic
(additionally, enteric nervous system)
Sympathetic : fight or flight
Parasympathetic: rest and digest
ganglia
clumps of cells (e.g. nerve cells)
lie outside of the PNS
preganglionic
lies within CNS
output to ganglia
post ganglionic
lies in PNS
output goes to effectors(muscles, glands, organs, etc)
Transmitters in preganglionic
cholinergic via nicotinic receptors (ionotropiic)
transmitters in postganglionic; sympathetic
noradrenergic
transmitters in postganglionic; parasympathetic
cholinergic via muscarinic receptors (metabotropic) mediated by G proteins
Sympathetic system
preganglionic cells live in…
preganglionic cells live in lateral horns in the thoracic and lumbar levels of the spinal cord
exit through ventral root
sympathetic ganglia lie in…
paravertebral sympathetic trunk (chain) - mostly
Remaining sympathetic ganglia (prevertebral gangli) tucked elsewhere
sympathetic preganglionic neurons are
tonically active
myelinated
run through spinal nerve
reach sympathetic chain ganglia via white communicating rami
((some travel outside of home ganglion to link to neighboring ganglia))
((exit through spinal nerves to reach prevertebral ganglia))
1 preganglionic sympathetic axon synapse onto ______ postganglionic sympathetic neurons
1 preganglionic sympathetic axon synapse onto many postganglionic sympathetic neurons
postganglionic neurons (either sympathetic paravertebral chain ganglia or prevertebral ganglia) have __________ axons
postganglionic neuronshave unmyelinated axons
postganglionic cells in sympathetic chain ganglia send axon via ________ or _______
gray communicating rami or other branches to reach the effectors
