21. Autonomics

Question 1

Where do visceral sensory and motor innervations go to?

Answer 1

Generally to structures in body cavities (but not always)

Question 2

Visceral sensory

Answer 2

Stimuli associated with blood vessels and internal organs

Question 3

Visceral motor (autonomic nervous system) characteristics

Answer 3

Unlike somatic motor, can excite or inhibit the target
Regulates below conscious level (deep to cortex): heart function, blood pressure, body temp, respiration, sweating, digestion, etc

Question 4

Visceral motor controls

Answer 4

Cardiac muscle (myocardium of heart)
Smooth muscle (digestive tract, bronchi, blood vessels, eye muscles)
Glands (salivary, digestive, lacrimal, sweat, sex glands)

Question 5

Similarities between somatic and visceral sensory neurons

Answer 5

Very similar
Both have single neuron pathway in PNS
Both have cell bodies in dorsal root ganglia and synapse in dorsal horn

Question 6

Somatic sensory indicates

Answer 6

Skin/body wall
Temp, pain, pressure, touch, proprioception
Easy to pinpoint

Question 7

Visceral sensory indicates

Answer 7

Organs in body cavity
Temp, pain, stretch (hunger, nausea, fullness, etc)
Unlocalized

Question 8

Somatic motor controls

Answer 8

Skeletal muscle
1 neuron pathway

Question 9

Visceral motor controls

Answer 9

Smooth, cardiac muscle, glands
2 neuron pathway- presynaptic neuron (preganglionic) and postsynaptic neuron (postganglionic)

Question 10

Sympathetic division used for

Answer 10

Greater physiological demand (exercise, fight or flight response)

Question 11

Parasympathetic division used for

Answer 11

Routine function
Maintain homeostasis
“Rest and digest”

Question 12

Where do sympathetic and parasympathetic neurons innervate?

Answer 12

Almost all of the same targets, but with opposite effects

Question 13

Components of autonomic nervous system

Answer 13

Craniosacral division and thoracolumbar division

Question 14

Craniosacral division neurons and neurotransmitters

Answer 14

Long pregangionic, short postganglionic neurons
Neurotransmitter: acetylcholine

Question 15

Thoracolumbar division neurons and neurotransmitters

Answer 15

Short pregangionic, long postganglionic neurons
Neurotransmitters: preganglipmic is acetylcholine and postganglionic is norepinephrine

Question 16

What cranial nerves have parasympathetic function

Answer 16

Oculomotor nerve (CN III)
Facial nerve (CN VII)
Glossopharyngeal nerve (CN IX)
Vagus nerve (CN X)

Question 17

Parasympathetics of oculomotor nerve (CN III)

Answer 17

Targets:
Pupil (constricts via sphincter pupillae muscle)
Lens (thickens via ciliary muscle)

Question 18

Parasympathetics of facial nerve (CN VII)

Answer 18

Targets:
Lacrimal gland to produce tears
Submandibular and sublingual salivary glands to produce saliva

Question 19

Parasympathetics of glossopharyngeal nerve (CN IX)

Answer 19

Targets parotid salivary gland to produce saliva

Question 20

Parasympathetics of vagus nerve (CN X)

Answer 20

Targets
Lungs (constrict bronchioles)
Heart (decrease heart rate)
GI tract (increase activity of digestive system)

Question 21

Parasympathetics of S2-S4

Answer 21

Targets pelvic organs and external genitalia

Question 22

Sympathetic target

Answer 22

Pupil (dilate)
Lens (thin)
Lacrimal gland (decrease tear production)
Salivary glands (decrease saliva production)
Lungs (dilate bronchioles)
Heart (increase heart rate)
GI tract (decrease activity of digestive system)
Sweat glands (produce sweat)

Question 23

Characteristics of the sympathetic trunk (chain)

Answer 23

Nerve “chain” with ganglia
Pre- and post-ganglionic sympathetic neurons synapse in ganglia
Allows for sympathetic neurons to travel up and down beyond thoracolumbar region

Question 24

Where are pre- and post- ganglionic sympathetic neurons’ cell bodies

Answer 24

Pre-ganglionic cell bodies in lateral horn of spinal cord between T1-L2
Ganglia in sympathetic trunk contain cell bodies of post-ganglionic neurons

Question 25

Sympathetic trunk connects …

Answer 25

To spinal nerves via short branches

Question 26

Targets of Sympathetics to body wall

Answer 26

Targets: sweat glands, blood vessels, and Arrector pili muscles (these targets do not have Parasympathetic innervation)

Question 27

Pathway of sympathetic to body wall

Answer 27

Pathway 1:
Preganglionic neuron enters sympathetic trunk
Synapses with postganglionic neuron in chain ganglion
Postganglionic neuron rejoins spinal nerve to body wall target

Question 28

Target of sympathetics to body cavity

Answer 28

Visceral organs (heart, digestive tract, kidneys, uterus)

Question 29

Pathway of sympathetics to body cavity

Answer 29

Pathway 2:
Preganglionic neuron enters sympathetic trunk
Joins splanchnic nerve
Synapses with postganglionic neuron at collateral ganglion
Postganglionic neuron travels to target

Question 30

What is fight or flight response

Answer 30

Sympathetic division responding to emergency situation

Question 31

Pathway of fight or flight response

Answer 31

Pathway 3:
Preganglionic neuron enters sympathetic trunk and pass through without synapsing
Preganglionic neuron travels directly to adrenal gland to synapse with cells in the medulla
Cells in adrenal medulla release epinephrine (Adrenalin) and norepinephrine directly into blood stream for rapid, systemic effect