M10 - Autonomic Nervous System

Question 1

Somatic nervous system

Answer 1

voluntary, skeletal muscles, 1 LMN, no synapse, high + rapid myelination, excites cells, origin at ventral horn

Question 2

Autonomic nervous system

Answer 2

Involuntary, cardiac and smooth muscles and glandular tissue, 2 LMN, synapse, lightly myelinated preganglionic, unmyelinated postganglionic, slow speed, can excite and inhibit, original at lateral horn

Question 3

Sympathetic ANS

Answer 3

Fight or flight, origin at thoracic and first 2 lumbar lvls of spinal cord, short preganglionic, long postganglionic, ganglia close to spinal cord in sympathetic trunk or prevertebral ganglia, widespread response, between pre and postganglionic neurons = acetylcholine, between post and effector = norepinephrine

Question 4

Parasympathetic ANS

Answer 4

Rest and digest, origin at brainstem and cranial nerves, long preganglionic, short postganglionic, terminal ganglia near target organ, intramural ganglia in wall of target organ, local response, between pre and postganglionic neurons = acetylcholine, between post and effector = acetylcholine

Question 5

Autonomic plexuses

Answer 5

Collections of sympathetic postganglionic axons, parasympathetic preganglionic axons, and visceral sensory axons
Sympathetic and parasympathetic axons travel together to reach destination

Question 6

Cranial nerves

Answer 6

Oculomotor (CN III), facial (CN VII), glossopharyngeal (CN IX), vagus (CN X) - innervates majority of thoracic and abdominal organs

Question 7

Pelvic splanchnic nerves

Answer 7

Emerge from sacral region, contribute to hypogastric plexus

Question 8

Vagus nerve

Answer 8

Cardiac, pulmonary, esophageal, celiac, superior mesenteric, inferior mesenteric plexus

Question 9

Cardiac plexus

Answer 9

Innervates heart, lowers heart rate

Question 10

Pulmonary plexus

Answer 10

Innervates lungs & bronchi, reduced respiratory rate and constriction of bronchi

Question 11

Esophageal plexus

Answer 11

Innervates smooth muscle in lower esophagus

Question 12

Celiac plexus

Answer 12

Innervates foregut organs - digestive tract from lower portion of esophagus thru first 2 parts of duodenum + accessory digestive organs

Question 13

Superior mesenteric plexus

Answer 13

Innervates midgut organs - 3rd part of duodenum thru first 2/3 of transverse colon

Question 14

Hypogastric plexus

Answer 14

Innervates abdominal and pelvic organs, leads to inferior mesenteric plexus and pelvic organs - bladder and reproductive organs

Question 15

Inferior mesenteric plexus

Answer 15

Innervates hindgut organs - digestive organs from last 1/3 of transverse colon to end of digestive tract

Question 16

Sympathetic division

Answer 16

Thoracolumbar division, fibers leave spinal cord thru thoracic and first 2 lumbar lvls, enter sympathetic trunk

Question 17

Sympathetic trunk

Answer 17

located lateral to vertebral column bilaterally, start in lateral horn thru ventral root to white rami communicantes, several options after that

Question 18

White rami communicantes

Answer 18

Preganglionic sympathetic axons of T1-L2 spinal nerves, myelinated, part of every single sympathetic pathway

Question 19

Gray rami communicantes

Answer 19

Postganglionic sympathetic axons from sympathetic trunk to spinal nerve, unmyelinated, only present in spinal nerve pathway

Question 20

Prevertebral ganglia

Answer 20

Collections of cell bodies immediately anterior to vertebral column on anterolateral surface of aorta, cluster around arteries
Celiac ganglia - foregut
Superior mesenteric ganglia - midgut
Inferior mesenteric ganglia - hindgut

Question 21

Spinal nerve pathway

Answer 21

Starts in lateral horn, thru ventral root into spinal nerve, thru white rami into sympathetic chain, synapse in sympathetic chain ganglia, postganglionic axon travels thru gray rami back to spinal nerve, origin of T1-L2, some fibers will travel to superior, middle, and inferior cervical ganglia, some will travel inferiorly to sacral portions, target is integumentary, innervates arrector pili muscles, sweat glands, and blood vessels

Question 22

Postganglionic sympathetic pathway

Answer 22

Cell body in lateral horn, thru ventral root into spinal nerve, thru white rami into sympathetic chain, ascend within sympathetic chain to superior, central, and inferior cervical ganglia, synapse in 1 of 3 ganglia, exit chain, origin of T1-T5

Question 23

Superior cervical ganglia

Answer 23

Go to head

Question 24

Middle and inferior cervical ganglia

Answer 24

Go to thoracic organs, travel thru cardiac (incr heart rate) & pulmonary (incr rate of respiration, dilating bronchi) & esophageal plexuses (smooth muscle of esophagus)

Question 25

Splanchnic nerve pathway

Answer 25

Largest and most complex, 1 vertebral ganglia that split into R and L, not bilateral, origins T5-L2, cell body in lateral horn, thru ventral root into spinal nerve, thru white rami to sympathetic chain, exit chain towards midline anterior to aorta

Question 26

Greater splanchnic nerve

Answer 26

T5-T9, go to celiac ganglion, foregut

Question 27

Lesser splanchnic nerve

Answer 27

T10-T11, superior mesenteric ganglion, midgut

Question 28

Least splanchnic nerve

Answer 28

T12, also to superior & inferior mesenteric ganglion, hindgut

Question 29

Lumbar splanchnic nerve

Answer 29

L1-L2, inferior mesenteric ganglion, hindgut

Question 30

Sacral extension of splanchnic nerve pathway

Answer 30

Synapse on postganglionic neurons within sympathetic chain, postganglionic neurons send fibers out to sacral splanchnic nerves, travel thru hypogastric plexus to pelvic organs

Question 31

Adrenal medulla pathway

Answer 31

Cell body in lateral horn, thru ventral root to spinal nerve, thru white rami to sympathetic chain, leave chain to adrenal medulla, origin T8-T12, no postganglionic neuron, secrete norepinephrine and epinephrine, help w coping for stress/danger

Question 32

Referred pain

Answer 32

Occurs when impulses from certain viscera are perceived as originating not from organ but in dermatome of skin