Ch17: The Nervous System: Autonomic Nervous System
The effects of the epinephrine and norepinephrine released by the suprarenal glands last longer than those of either chemical when released at neuroeffector junctions. Why?
There are no enzymes to break down epinephrine and norepinephrine in the blood and very little in peripheral tissues.
In some severe cases, a person suffering from stomach ulcers may need to have surgery to cut the branches of the vagus nerve that innervates the stomach. How would this help the problem?
Cutting off autonomic nervous system stimulation to the stomach through the vagus nerve decreases stimulation of digestive glands, thus reducing their secretion. This may diminish ulcers in the wall of the stomach.
Kassie is stung on the neck by a wasp. Because she is allergic to wasp venom, her throat begins to swell and her respiratory passages constrict. Would acetylcholine or epinephrine be more helpful in relieving her symptoms? Why?
Kassie should be treated with epinephrine. This would mimic sympathetic activation, which dilates air passageways in the lungs. The constriction of her respiratory passages would be alleviated.
acetylcholine a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
a) all preganglionic fibers
Damage to the ventral roots of the first five thoracic spinal nerves on the right side of the body would interfere with the ability to a) dilate the right pupil b) dilate the left pupil c) contract the right biceps brachii muscle d) contract the left biceps brachii muscle
a) dilate the right pupil
All preganglionic autonomic fibers release _______ at their synaptic terminals, and the effects are always a) norepinephrine; inhibitory b) nonrepinephrine; excitatory c) acetylecholine; excitatory d) acetylecholine; inhibitory
c) acetylecholine; excitatory
preganglionic a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
c) first neuron
Which of the following ganglia belong to the sympathetic division of the ANS? a) otic ganglion b) sphenopalatine ganglion c) paravertebral ganglia d) all of the above
c) paravertebral ganglia
The large cells in the suprarenal medulla, which resemble neurons in sympathetic ganglia, a) are located in the suprarenal cortex b) release acetylocholine into blood capillaries c) release epinephrine and norepinephrine into blood capillaries d) have no endocrine functions
c) release epinephrine and norepinephrine into blood capillaries
Cutting the ventral root of the spinal nerve at L2 would interrupt the transmission of what type of information? a) voluntary motor output b) ANS motor output c) sensory input d) a and b are correct
d) a and b are correct
The neurotransmitter at all synapses and neuroeffector junctions in the parasympathetic division of the ANS is a) epinephrine b) cyclic-AMP c) norepinephrine d) acetylocholine
d) acetylocholine
The white ramus communicans a) carries the postganglionic fibers to the effector organs b) arises from the dorsal root of the spinal nerves c) has fibers that do not diverge d) carries the preganglionic fibers into a nearby sympathetic chain ganglion
d) carries the preganglionic fibers into a nearby sympathetic chain ganglion
prevertebral a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
d) collateral ganglia
If the visceral signal from the small intestine does not reach the spinal cord, which structures might be damaged? a) preganglionic neurons b) white rami communicantes c) gray rami communicantes d) none of the above is correct
d) none of the above is correct
Visceral motor neurons in the CNS a) are ganglionic neurons b) are in the dorsal root ganglion c) have unmyelinated axons except in the lower thoracic region d) send axons to synapse on peripherally located ganglionic neurons
d) send axons to synapse on peripherally located ganglionic neurons
epinephrine a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
e) suprarenal medulla
What alterations in ANS function would lead a clinician to diagnose a condition of Horner's syndrome?
Horner's syndrome is caused by damage to the sympathetic postganglionic innervation to one side of the face. Symptoms, typically limited to the affected side, include facial flushing, an inability to sweat, a markedly constricted pupil of the eye, drooping eyelids, and a sunken appearance of the eye.
paravertebral a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
I) sympathetic chain
How do sympathetic chain ganglia differ from both collateral ganglia and intramural ganglia?
Sympathetic chain ganglia are innervated by preganglionic fibers from the thoracolumbar regions of the spinal cord, and they are interconnected by preganglionic fibers and axons from each ganglion in the chain innervating a particular body segment. The collateral ganglia are part of the abdominal autonomic plexuses anterior to the vertebral column. Preganglionic sympathetic fibers innervate the collateral ganglia as splanchnic nerves. Intramural ganglia (also termed terminal ganglia) are part of the parasympathetic division. They are located near or within the tissues of the visceral organs.
Why are the effects of parasympathetic stimulation more specific and localized than those of the sympathetic division?
The parasympathetic division innervates only visceral structures served by some cranial nerves or lying within the thoracic and/or abdominopelvic cavities. The sympathetic division has widespread impact due to extensive collateral branching of preganglionic fibers, which reach visceral organs and tissues throughout the body.
Compare the general effects of the sympathetic and parasympathetic divisions of the ANS.
The sympathetic division of the ANS stimulates metabolism, increases alertness, and prepares for emergency in "fight or flight." The parasympathetic division promotes relaxation, nutrient uptake, energy storage, and "rest and repose."
Describe the general organization of the pathway for visceral motor output.
Visceral motor neurons, called preganglionic neurons, send their axons, called preganglionic fibers, from the CNS to synapse on ganglionic neurons, whose cell bodies are located in ganglia outside the CNS.
Splanchnic nerves a) are formed by parasympathetic postganglionic fibers b) include preganglionic fibers that go to collateral ganglia c) control sympathetic function of structures in the head d) connect one chain ganglion with another
b) include preganglionic fibers that go to collateral ganglia
splanchic a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
b) preganglionic fibers to collateral ganglia
Sympathetic preganglionic fibers are characterized as being a) short in length and unmyelinated b) short in length and myelinated c) long in length and myelinated d) long in length and unmyelinated
b) short in length and myelinated
What anatomical mechanism is involved in causing a person to blush? a) blood flow to the skin is increased by parasympathetic stimulation b) sympathetic stimulation relaxes vessel walls, increasing blood flow to the skin c) parasympathetic stimulation decreases skin muscle tone, allowing blood to pool at the surface d) sympathetic stimulation increases respiratory oxygen uptake, making the blood brighter red
b) sympathetic stimulation relaxes vessel walls, increasing blood flow to the skin
Postganglionic fibers of autonomic neurons are usually a) myelinated b) unmyelinated c) larger than preganglionic fibers d) located in the spinal cord
b) unmyelinated
Preganglionic fibers of the ANS sympathetic division originate in the a) cerebral cortex of the brain b) medulla oblongata c) brain stem and sacral spinal cord d) thoracolumbar spinal cord
d) thoracolumbar spinal cord
crisis a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
f) sympathetic activation
thoracolumbar a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
g) sympathetic division
parasympathetic a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
h) terminal ganglia
sympathetic a) all preganglionic fibers b) preganglionic fibers to collateral ganglia c) first neuron d) collateral ganglia e) suprarenal medulla f) sympathetic activation g) sympathetic division h) terminal ganglia I) sympathetic chain j) long postganglionic fiber
j) long postganglionic fiber
