Chapter 14 Flashcards
Characteristics of the autonomic nervous system
Motor to smooth muscle, cardiac muscle, and glands
Involuntary
Two divisions
Use 2 motor neurons out of the CNS
Sympathetic nervous system characteristics
widespread, branches, expend energy in emergency situations, fight or flight, stress
What neurotransmitter does the sympathetic nervous system use
norepinephrine
Parasympathetic nervous system characteristics
smaller, localized, conserve and store energy, rest and digest, peace
What neurotransmitter does the parasympathetic nervous system use
ACh
Are the pre and post ganglionic motor neurons myelinated?
Preganglionic motor neuron is lightly myelinated, the postganglionic motor neuron is not myelinated
Ganglia
a collection of neuron cell bodies outside the CNS
Where is sympathetic ganglia found
found near the spinal cord
Sympathetic pre and post ganglion
Preganglionic = short, ACh
Postganglionic = long, norepinephrine
Parasympathetic pre and post ganglion
Preganglionic = long, ACh
Postganglionic = short, ACh
What is the sympathetic systems output
thoracolumbar (region of the spinal cord)
What connects sympathetic ganglia to spinal nerves
communicating rami
Where are myelinated preganglionic motor neurons found
white ramus (lateral)
Where are unmyelinated postganglionic motor neurons found
gray ramus (medial)
What 3 things do preganglionic fibers do
1.) synapse in the same ganglion
2.) synapse in higher or lower ganglion
3.) pass through sympathetic chain ganglia to go to collateral/pre-vertebral ganglion
What 3 areas are postganglionic neurons found
spinal nerves, sympathetic nerves, splanchnic nerves
Where are postganglionic neurons found in spinal nerves
skin, body surface, blood vessels
Where are postganglionic neurons found in sympathetic nerves
head, organs of thoracic region
Where are postganglionic neurons found in splanchnic nerves
abdominal and pelvic organs
What is the adrenal medulla
a highly modified ganglion
What does the adrenal medulla do
release hormones into the blood
where do epinephrine and norepinephrine function
on the same receptor
What is the parasympathetic system output
craniosacral (brain and lower region of the spinal cord) S2-S4
What cranial nerves does the parasympathetic nervous system use
oculomotor (3), facial (7), glossopharyngeal (9), vagus (10)
What are the norepinephrine receptors in the sympathetic system
Alpha 1, alpha 2, beta 1, beta 2, beta 3
Alpha 1 receptor
blood vessels, most organs (not the heart)
Alpha 2 receptor
CNS, act to decrease sympathetic output
Beta 1 receptor
heart, act to increase heart rate and force
Beta 2 receptor
lungs, act to dilate tubes and decrease mucus (breathe better faster)
Beta 3 receptor
Fat (adipose tissue), act to breakdown fat to release energy
What receptor does the parasympathetic system use
muscarinic receptor as a second messenger receptor
Dual innervation
both the sympathetic and parasympathetic system are opposing/antagonizing the other
Tone
organs that have one system that predominates
What causes neurogenic shock
No parasympathetic input, decreasing sympathetic tone
