Autonomic nervous system (ANS) exam 4: final exam Flashcards
what is the function of the Autonomic nervous system?
controls body processes, not under conscious control. example: heart rate, blood pressure, digestion, pupil dilation/constriction
what is the sympathetic division?
it is a division of the ANS. it gets body ready for physical activity. fight or flight response
what is the parasympathetic division?
calms body after fight or flight is over, also controls body functions at rest
what is the structure of the ANS divisions?
for both divisions it takes 2 neurons to get from the CNS to target organs
1) preganglionic neuron-
what is preganglionic neuron?
cell body in CNS, axon travels in a nerve to an autonomic ganglion, forms synapse with postganglionic neuron
what is postganglionic neuron?
has cell body is autonomic ganglion, axon travels in a nerve to target organ synapses with cells of target organ
what is the structure of the parasympathetic division?
all parasympathetic preganglionic axons start in the brain or end of spinal cord and travel in cranial or sacral nerves
what is parasympathetic ganglia?
a) intramural ganglia- most ganglia are in walls of target organs post ganglionic neurons are really short
b) if the target organ is small the ganglion is outside organ
how many cranial nerves contain parasympathetic axons?
out of the 12 cranial nerves only 4 contain parasympatheric axons
what cranial nerve controls the iris and contains parasympathetic axons?
occumotor nerve 3rd cranial nerve, uses ciliary ganglion in eye socket
when someone is interested in u pupils dilate
pararsympathetic nerves
what does the facial cranial nerve that has parasympathetic axons do?
controls salivary glands, tear glands, mucus glands, has 2 ganglia, spheropalatine ganglia, submandibular ganglia
what cranial nerve contains parasympathetic axons that controls salivary gland uses otic ganglion?
glossoparyngeal nerve
what cranial nerve has parasympathetic axons that controls organs of thorax and abdomen and uses intramural ganglia?
vaugus nerve
what do the sacral nerves do in parasympathetic ganglia?
the parasympathetic preganglionic axons exit spinal cord in ventral rami of spinal nerves 2, 3, 4 they travel to target organs of pelvis in pelvic splanchnic nerves uses intramural ganglia
what is the structure of the preganglionic axons in the sympathetic division?
exit spinal cord in ventral rami of spinal nerves T1-L2
what is the structure of the chain in ganglia of the sympathetic division?
on both sides of spinal cord attached to spinal cord by a branch from ventral rami of spinal nerves attached to each other by sympathetic trunks (short nerves)
what is prevertebral ganglia?
sits on aorta, short nerves connect prevertebral ganglia forming plexuses
what are nerve fiber pathways?
all sympathetic preganglionic axons exit spinal cord in ventral rami of spinal nerves and enters nearest chain ganglia 4 options
what is two of the options for the nerve fiber pathways?
- preganglionic axon can synapse in that ganglion
- preganglionic axon can pass thru chain ganglia goes to prevertebral ganglia and synapses there
what are two more options for the nerve fiber pathways?
- enter nearest chain ganglia and travel up or down in different chain ganglia and synapse there
- preganglionic axon can travel down to a lower chain ganglia pass thru a synapse in a prevertebral ganglia
what is the sympathetic pathway to the head?
preganglionic nerve fibers exit spinal cord in ventral rami of spinal nerves T1-T4 enter nearest chain ganglia
travel up to most superior cervical chain ganglion and synapse there
post ganglionic axons travel from ganglia and target organs
what is the sympathetic pathways to the thorax?
preganglionic axons leave spinal cord in ventral rami of spinal nervesT1-T6
enter nearest chain ganglia
fibers controlling lings synapse here
fibers controlling heart travel up to cervical chain ganglia and synapse there
postganglionic axons travel from ganglia to target organ
what is the sympathetic pathway to the abdomen?
preganglionic axons leave spinal cord in the ventral rami of spinal nerves T5-L2, enter nearest chain ganglia, pass thru and travel to prevertebral ganglia in greater and lesser splanhnic nerves synapse in pre vertebral ganglia
postganglionic axons leave ganglia and travel to target organs
what is the sympathetic pathways to the pelvis?
preganglionic axons exit spinal cord in ventral rami of spinal nerves in T10-L2
enter nearest chain ganglia and descent to lumbar and sacral chain ganglia
other axons pass through (no synapse) and travel to pre vertebral ganglia in lumbar splahnic nerves and synapse in prevertebral ganglia
postganglionic axons travel from ganglia to target organs
what releases hormones to cause fight or flight effect?
adrenal medulla
what is the structure of the adrenal medulla?
inner part of adrenal gland made of neural tissue, cell bodies with no axons
gets input from preganglionic axons that exit spinal cord in ventral rami of spinal nerves t6-t11
