autonomic nervous system (ch 14) Flashcards
autonomic means
self governed
general aspects of the autonomic nervous system
- motor to smooth muscle, cardiac muscle, glands
- involuntary
two divisions of the autonomic nervous system
sympathetic and parasympathetic
the sympathetic division is
a widespread system with numerous and early branches
function of the sympathetic division
fight or flight, gearing up to expend energy in an emergency
the parasympathetic division is
a smaller, more localized system
function of the parasympathetic division
rest and digest, involved in conserving/storing energy
how many motor neurons come out of the CNS
two - preganglionic and postganglionic
preganglionic motor neurons are
from the CNS to autonomic ganglion, secrete Ach onto a nicotinic receptor in the Na+/K+ ion channel, is lightly myelinated
postganglionic motor neurons are
from the ganglion to the effector, is unmyelinated
NTs for each effector
sympathetic - NE
parasympathetic - ACh
where are ganglia located
sympathetic - usually near spinal cord (pre - short, post - long)
parasympathetic - near/in effector (pre - long, post - short)
output of the sympathetic system
thoracolumbar (regions of the spinal cord)
sympathetic chain ganglia are
paravertebral
the sympathetic goes through
communicating rami that connect sympathetic ganglia to spinal nerves
neurons of the white ramus are
myelinated and preganglionic
neurons/axons of the gray ramus are
unmyelinated and postganglionic
preganglionic fibers may do three things:
- synapse in the same ganglion
- synapse in a higher or lower ganglion
- pass through sympathetic chain ganglia to go to collateral (prevertebral) ganglion
postganglionic axons are found in
- spinal nerves
- sympathetic nerves
- splanchnic nerves