BSC2086 Ch. 11 Review
Sympathetic preganglionic neurons exit the spinal nerve via the ________ before they enter the ________.
white ramus : ganglion of the sympathetic trunk
Which of the following is NOT a visceral reflex?
withdrawal reflex
Binding of norepinephrine to what type of receptor will trigger the activation of phospholipase C?
α1
What type of receptor agonists are used to treat people suffering from asthma or nasal congestion?
β2
What class of adrenergic receptor activates the enzyme adenylate cyclase?
beta1, beta2, and beta3
Compared to norepinephrine, epinephrine has a greater affinity for what type of receptor?
beta2
Dual innervation of organs by the autonomic nervous system refers to the observation that ________.
both sympathetic and parasympathetic neurons innervate most organs
Where are most of the autonomic nervous system control centers located?
brainstem
Where in the central nervous system do the preganglionic neurons of the parasympathetic nervous system originate?
brainstem and sacral region of the spinal cord
Which of the following physiological responses are associated with an elevation in parasympathetic nervous system activity?
enhanced absorption of nutrients
In what class of neuron and within what organelle is the enzyme monoamine oxidase located?
mitochondria of sympathetic postganglionic neurons
What cholinergic receptors are coupled to G proteins?
muscarinic
Binding of acetylcholine to ________ receptors causes a ________ by opening channels that permit both sodium and potassium to permeate the membrane
nicotinic : depolarization
Which class of autonomic nervous system receptors is ionotropic?
nicotinic cholinergic
Which of the following contributes to the ability of the sympathetic nervous system to produce widespread responses within the body?
one preganglionic neuron sends collaterals to multiple ganglia, affecting multiple postganglionic neurons
The autonomic nervous system innervates all the following effector organs and tissues except ________.
skeletal muscles
Which of the following neurons of the efferent branch of the peripheral nervous system does NOT release acetylcholine?
sympathetic postganglionic neuron
The balance between sympathetic and parasympathetic activity is modified primarily by ________.
the activity of the body
Which of the following structures of an autonomic neuron is NOT located within the ganglion?
the cell body of preganglionic neurons
Which of the following are indicative of the relative release of catecholamines from the adrenal medulla?
80% epinephrine : 20% norepinephrine
At rest, what is the relative contribution of the sympathetic and parasympathetic nervous systems to the regulation of homeostasis?
Both systems are active but the parasympathetic predominates
When the body is stressed, what is the relative contribution of the sympathetic and parasympathetic nervous systems to the regulation of homeostasis?
Both systems are active but the sympathetic predominates
The gray ramus is comprised of what fiber type?
C
Which of the following descriptions of collateral ganglia is true?
Collateral ganglia are in the sympathetic nervous system but distinct from the sympathetic chain, and they function as a site of communication between sympathetic preganglionic neurons and postganglionic neurons.
Which of the following descriptions is TRUE for the parasympathetic nervous system, but NOT the sympathetic nervous system?
Postganglionic fibers release acetylcholine
Which of the following cranial nerves does NOT include parasympathetic nerves?
V - trigeminal nerve
What are swellings of postganglionic autonomic axons from which neurotransmitters are released called?
Varicosities
What type of channels that are present within the varicosities of autonomic neurons are absent from the axon terminal of other neurons?
Voltage-gated Na+ and K+ channels
Parasympathetic neurons from which cranial nerve innervate most of the viscera in the thoracic and abdominal cavities?
X
Parasympathetic preganglionic neurons release the neurotransmitter ________; sympathetic preganglionic neurons release the neurotransmitter ________.
acetylcholine : acetylcholine
Parasympathetic postganglionic neurons release the neurotransmitter ________; sympathetic postganglionic neurons release the neurotransmitter ________.
acetylcholine : norepinephrine
What enzyme degrades the neurotransmitter released from varicosities of parasympathetic postganglionic neurons?
acetylcholinesterase
Which of the following endocrine glands is innervated by sympathetic preganglionic neurons?
adrenal medulla
Activation of which class of adrenergic receptor will result in calcium release from intracellular stores?
alpha1 only
Actions at which class of adrenergic receptor generally have excitatory effects?
alpha1, alpha2, beta1, and beta3
Activation of which class of adrenergic receptor decreases the cytosolic levels of cAMP?
alpha2 only
Which of the regions of the brain listed below is NOT involved in the control of the autonomic nervous system?
cerebellum
What cells of the adrenal medulla release epinephrine?
chromaffin cells
Parasympathetic preganglionic neurons travel in what nerves?
cranial and pelvic nerves
Which of the following does NOT have nicotinic cholinergic receptors?
effector organs for the parasympathetic nervous system
What area of the brain initiates the fight-or-flight response by producing widespread activation of the sympathetic nervous system?
hypothalamus
Which of the following physiological responses are associated with elevated sympathetic nervous system activity?
increased contractile force of the heart
Within the autonomic ganglia, what are the cells that modulate the flow of information to the target organ called?
intrinsic neurons
Where do the preganglionic neurons of the sympathetic nervous system emerge from the spinal cord?
thoracic and lumbar regions
Which of the following best describes the general arrangement of the efferent limb of the autonomic nervous system?
two neurons in series
The presence of ________ within varicosities mediate the release of neurotransmitter.
voltage-gated Ca2+ channels
