Chapter 15 Autonomic Nervous System
autonomic nervous system
= visceral motor effectors of smooth muscle, cardiac muscle, and glands. controls vital bodily functions w/o consciousness.
sacral outflow
S2 - S4 spinal nerves, which are also called pelvic splanchnic nerves. connects to second 1/2 of large intestine, rectum, urinary bladder, ureters, and reproductive organs.
branching of sympathetic
a lot
neurotransmitter of parasympathetic
acetylcholine
Parasympathetic division of ANS
also called craniosacral division (composed of cranial and sacral nerves). for normal maintenance, i.e., "Rest and digest" = refueling, removal.
inferior cervical ganglion
also called stellate ganglion. connects to heart
sympathetic division of ANS
also called the Thoraco-Lumbar division. from T1 to L2. "fight or flight" = emergency, excitement, exercise.
adrenal medulla
an extension of the sympathetic division. inner part of the adrenal gland located on top of the kidney. made of postganglionic sympathetic cells.
cell bodies of parasympathetic
brain steam and sacral spinal cord
lumbar ganglia
connects to abdomen
superior cervical ganglion
connects to head
middle cervical ganglion
connects to salivary glands and heart
blood vessels to skin: Sympathetic
constrict
urinary bladder: parasympathetic
constrict
iris: parasympathetic
constricts
sphincters: Sympathetic
contract
cranial outflow of parasympathetic
cranial nerves 3, 7, 9, 10. these cranial nerves originate in the dorsal motor nucleus of the medulla.
digestive functions: Sympathetic
decreases
heart rate: parasympathetic
decreases
respiratory rate: parasympathetic
decreases
blood vessels to muscles: Sympathetic
dilate
iris: Sympathetic
dilates
digestive functions: parasympathetic
increase
heart rate: Sympathetic
increases
respiratory rate: Sympathetic
increases
adrenal medulla: Sympathetic
increases production of epinephrine
white ramus communicans
lateral and have myelin. goes to ganglion and contains pre-ganglionic axon
cell bodies of sympathetic
lateral horn T1-L2
direction of impulse
lateral horn to ventral root to spinal nerve to ramus communicans to ganglions
hypothalamus is affected by...
limbic system: emotions and cerebral cortex - frontal lobe: thoughts
postganglionic axons of sympathetic
long in length
chromaffin cells
main cells of the adrenal medulla. secrete norepinephrine and epinephrine.
hypothalamus
main integration center of ANS function
gray ramus communicans
medial and without myelin. comes from ganglion and contains post-ganglionic axon
sympathetic trunk (chain) ganglia
meeting place of pre- and post-ganglionic axons. located next to vertebral column.
ganglion of sympathetic
near CNS
blood vessels to muscles, blood vessels to skin and the adrenal medulla: parasympathetic
no parasympathetic control
neurotransmitter of sympathetic
norepinephrine
ganglion of parasympathetic
on effector organ
2nd neuron
post-ganglionic axon; cell body located in autonomic ganglion; synapses with target cells / organ
1st neuron
pre-ganglionic axon; cell body located in spinal cord or brain
CN III - oculomotor nerve
pupil constriction for iris. controlled focus for ciliary muscle.
sphincters: parasympathetic
relax
urinary bladder: Sympathetic
relaxes
CN IX - glossopharyngeal nerve
saliva is produced by parotid gland.
postganglionic axons of parasympathetic
short in length
CN VII - facial nerve
tears are produced by lacrimal gland. saliva is produced by submandibular gland and sublingual gland.
CN X - vagus nerve
to all organs of the thorax, abdomen, and first half of large intestine.
branching of parasympathetic
very little
response of parasympathetic
very local
visceral reflex arc
visceral sensory to CNS to visceral motor to organs. ANS is motor portion of visceral reflex arc
response of sympathetic
widespread
