Autonomic Nervous System (ANS) - Chapter 18

Question 1

The ANS governs what kind of actions?

Answer 1

involuntary

Question 2

Are the functions of the ANS voluntary or involuntary?

Answer 2

involuntary

Question 3

Which neurons of the ANS innervate smooth and cardiac muscle and glands?

Answer 3

motor neurons

Question 4

Which neurons can excite or inhibit cells in the viscera?

Answer 4

motor neurons

Question 5

The first neuron in an ANS pathway is called the what?

Answer 5

preganglionic neuron

Question 6

The second neuron in the ANS pathway is called the what?

Answer 6

postganglionic neuron

Question 7

Where is the cell body of the preganglionic neuron located?

Answer 7

brain or spinal cord

Question 8

Where is the postganglionic neuron housed/located?

Answer 8

within an autonomic ganglion in PNS

Question 9

The postganglionic axon extends to where?

Answer 9

effector (target) cells

Question 10

What is the role of the parasympathetic division?

Answer 10

conservation of energy and replenishment of nutrient stores (“rest-and-digest”)

Question 11

What is the role of the sympathetic division?

Answer 11

preparation of the body for emergencies (“fight-or-flight”)

Question 12

Describe the length of the pre- and post-ganglionic axons in the sympathetic division.

Answer 12

preganglionic axon = short, postganglionic axon = long

Question 13

Describe the length of the pre- and post-ganglionic axons in the parasympathetic division.

Answer 13

preganglionic axon = long, post ganglionic axon = short

Question 14

Which division is responsible for a global response?

Answer 14

sympathetic (“fight-or-flight”)

Question 15

Which division is responsible for a local response?

Answer 15

parasympathetic (“rest-and-digest”)

Question 16

Where are ganglionic neurons found? (2 possible locations)

Answer 16

in terminal ganglia close to the target organ or intermural ganglia in the wall of the target organ

Question 17

Which cranial nerves are part of the parasympathetic division?

Answer 17

• oculomotor nerve (CN III)
• facial nerve (CN VII)
• glossopharyngeal nerve (CN XI)
• vagus nerve (CN X)

Question 18

The preganglionic neuron cell bodies in the thoracolumbar division of the sympathetic division are housed where?

Answer 18

in lateral horn between T1 and L2

Question 19

What does the sympathetic trunk ganglia house?

Answer 19

sympathetic ganglionic neuron cell bodies

Question 20

The cervical portion of the sympathetic trunk is partitioned into 3 ganglia, what are they?

Answer 20

superior, middle, and inferior ganglia

Question 21

What does the cervical sympathetic ganglia innervate?

Answer 21

structures in the head and neck

Question 22

The middle and inferior cranial ganglia house what?

Answer 22

neuron cell bodies that extend axons to the thoracic viscera

Question 23

What does the rami communicantes connect?

Answer 23

sympathetic trunk to each spinal nerve

Question 24

What does the white rami communicantes contain?

Answer 24

preganglionic sympathetic axons - myelinated

Question 25

What does the gray rami communicantes contain?

Answer 25

postganglionic sympathetic axons - unmyelinated

Question 26

What are splanchnic nerves composed of?

Answer 26

preganglionic sympathetic axons that did not synapse in a sympathetic trunk ganglion

Question 27

What are larger nerves that extend from the sympathetic trunk ganglia? (5)

Answer 27

- greater thoracic splanchnic nerves - lesser thoracic splanchnic nerves - least thoracic splanchnic nerves - lumber splanchnic nerves - sacral splanchnic nerves

Question 28

Splanchnic nerves usually terminate where?

Answer 28

prevertebral (collateral) ganglia

Question 29

Prevertebral ganglia include which ganglia?

Answer 29

celiac ganglia, superior mesenteric ganglia, and inferior mesenteric ganglia

Question 30

Where is the celiac ganglion located?

Answer 30

adjacent to origin of celiac artery

Question 31

Where is the superior mesenteric ganglion located?

Answer 31

adjacent to origin or superior mesenteric artery

Question 32

Where is the inferior mesenteric ganglion located?

Answer 32

adjacent to origin of inferior mesenteric artery

Question 33

Preganglonic axons of the celiac ganglion carry which nerves?

Answer 33

greater thoracic splanchnic nerves

Question 34

Postganglionic axons of the celiac ganglion innervate which parts of the body?

Answer 34

stomach, spleen, liver, gallbladder, proximal duodenum, part of pancreas

Question 35

Preganglionic axons of the superior mesenteric ganglion carry which nerves?

Answer 35

lesser thoracic splanchnic nerves

Question 36

Postganglionic axons of the superior mesenteric ganglion innervate which parts of the body?

Answer 36

distal duodenum, part of the pancreas, the remainder of small intestine, proximal large intestine, kidneys, part of ureters

Question 37

Preganglionic axons of the inferior mesenteric carry which nerves?

Answer 37

lumbar splanchnic nerves

Question 38

Postganglionic axons of the inferior mesenteric ganglion innervate which parts of the body?

Answer 38

distal colon, rectum, urinary bladder, distal ureter, and most reproductive organs

Question 39

Axons exit the sympathetic trunk ganglia by which 4 pathways?

Answer 39

- spinal nerve pathways -postganglionic sympathetic nerve pathway - splanchnic pathway - adrenal medulla pathway

Question 40

Which 2 pathways are the most common axon exits from the sympathetic trunk ganglia?

Answer 40

- spinal nerve pathway - postganglionic sympathetic nerve pathway

Question 41

Spinal cord to effectors; which pathway?

Answer 41

spinal nerve pathway

Question 42

spinal cord to thoracic cavity, internal organs, and effectors of skin of head; which pathway?

Answer 42

postganglionic sympathetic nerve pathway

Question 43

spinal cord to abdominal and pelvic organs; which pathway?

Answer 43

splanchnic pathway

Question 44

spinal cord to direct innervation of adrenal medulla; which pathway?

Answer 44

adrenal medulla pathway

Question 45

What is the purpose of the adrenal medulla?

Answer 45

release hormones within the bloodstream to promote flight-or-flight response

Question 46

Which hormones does the adrenal medulla release?

Answer 46

epinephrine and norepinephrine

Question 47

What are autonomic plexuses?

Answer 47

collections of sympathetic postganglionic axons, paraganglionic and preganglionic axons, and visceral axons

Question 48

Name autonomic plexuses (5):

Answer 48

- Cardiac plexus - Pulmonary plexus - Esophageal plexus - Abdominal plexus - Hypogastric plexus

Question 49

What does the cardiac plexus consist of?

Answer 49

postganglionic sympathetic axons from thoracic sympathetic trunk ganglia and preganglionic axons of vagus nerve

Question 50

Increasing sympathetic activity of cardiac plexus results in what?

Answer 50

increase heart rate and blood pressure

Question 51

Increasing parasympathetic activity results in what?

Answer 51

decrease heart rate

Question 52

What does the pulmonary plexus consist of?

Answer 52

postganglionic sympathetic axons from thoracic sympathetic trunk ganglia and preganglionic axons from the vagus nerve

Question 53

What does parasympathetic stimulation cause in the pulmonary plexus?

Answer 53

bronchoconstriction and increased mucus gland secretion in bronchial tree

Question 54

Sympathetic innervation of pulmonary plexus causes what?

Answer 54

brochiodilation

Question 55

What is dual innervation?

Answer 55

innervation by postganglionic axons from both ANS divisions

Question 56

What is the antagonistic effect?

Answer 56

actions of the ANS divisions usually oppose each other

Question 57

What does the esophageal plexus consist of?

Answer 57

preganglionic axons from the vagus nerve

Question 58

What does parasympathetic activity of the esophageal plexus result in?

Answer 58

coordinates smooth muscle activity during swallowing reflex in inferior wall and cardiac sphincter in inferior esophagus

Question 59

What is the abdominal aortic plexus composed of?

Answer 59

postganglionic axons projecting from the prevertebral ganglia and preganglionic axons from the vagus nerve

Question 60

What does the hypogastric plexus consist of?

Answer 60

postganglionic sympathetic axons and preganglionic parasympathetic axons from the pelvic splenic nerve

Question 61

What does the hypogastric plexus innervate?

Answer 61

viscera within the pelvic region