Somatic/Autonomic Nervous System
Some blood vessels contain alpha adrenergic receptors that cause vasoconstriction in the presence of epinephrine, whereas others have β2 adrenergic receptors that cause vasodilation in the presence of epinephrine.
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Motion sickness is probably caused by miscommunication between which of the following systems?
Autonomic and Vestibular and proprioceptive
Both alpha-bungarotoxin and curare are chemical agents that bind to the same neurotransmitter receptor, but only curare binds reversibly. Which of the locations listed would not be a location for this receptor?
Cardiac muscle, smooth muscle, and glands
The autonomic nervous system is involved in which of the following actions?
Fight or flight, pupil dilation or constriction, and urination, swallowing
The binding of acetylcholine to muscarinic receptors causes __________.
G protein activation
Which of the following organs is/are controlled by both the sympathetic and parasympathetic branches of the autonomic nervous system?
Heart urinary bladder Pancreas Lungs
Which of the following is likely to occur when someone stands up quickly?
Increased release of norepinephrine and increased activity at adrenergic receptors
With paralytic chemical agents or drugs, such as curare, what factor must be taken into consideration to keep the patient alive?
Interference at the neuromuscular junction can cause paralysis of the respiratory muscles.
Which of the following statements about the autonomic nervous system is(are) true?
Most of the functions of the autonomic nervous system are accomplished through visceral reflexes and the sympathetic and parasympathetic nervous systems tend to have opposing effects. The sympathetic and parasympathetic nervous systems function together to maintain homeostasis.
What type of drug would decrease heart rate?
Muscarinic agonist
Both alpha-bungarotoxin and curare are chemical agents that bind to the same neurotransmitter receptor, but only curare binds reversibly. Which receptor type is involved?
Nicotinic acetylcholine receptor
Bill contracts a viral disease that destroys cells in the anterior gray horns in his spinal cord. As a result, which of the following could you expect to happen in Bill?
Possible problems with moving his arms and problems with moving his legs
Which of the following cell types can be found in both the sympathetic and the parasympathetic nervous system?
Preganglionic neurons and chain ganglia
If a person has a genetic disorder that caused him/her to not produce norepinephrine, which type of tissue would be affected the least?
Skeletal muscle
During strenuous exercise, which of the following are likely to be more active?
Sympathetic nervous system and somatic nervous system
Similarities between autonomic neuroeffector synapses and the neuromuscular junction include __________.
The presence of enzymes such as acetylcholinesterase or monoamine oxidase and the requirement for calcium to produce transmitter release
Which of the following statements about the activation of adrenergic receptors in the sympathetic nervous system are true?
The receptors are always more sensitive to norepinephrine than epinephrine and the cellular responses to adrenergic receptor activation always inolve cAMP. The effects on the target organ are always excitatory.
Compare and contrast the voltage-gated sodium and potassium channels. What type of change in the cell is produced by ion movement through each type of channel?
The voltage-gated sodium channel opens in response to threshold voltage and allows sodium to enter the cell, thereby depolarizing the membrane potential and the potassium channel is also opened by threshold voltage and allows potassium to exit the cell, repolarizing or hyperpolarizing the membrane potential
End-plate potentials at the neuromuscular junction are similar to excitatory postsynaptic potentials in which of the following way(s)?
They are depolarizing.
Which of the following cell types or structures can be found in both the sympathetic and the parasympathetic nervous system?
Urinary bladder Pancreas Heart and urinary bladder Lungs Heart
To perform surgery with a minimum of pain for the patient and hassle for the surgeon, a patient may be administered a general anesthetic to prevent sensation and consciousness, as well as a paralytic agent to prevent reflexive muscle spasms. From what you have learned of motor control, which of the mechanisms below describes how a paralytic can prevent muscle contraction?
Virtually any drug that interferes with motor neuron activity at the neuromuscular junction could accomplish this.
The motor end plate is __________.
a folded area of muscle cell membrane with nicotinic ACh receptors clustered at the top of each fold
A motor unit consists of __________.
a motor neuron and all of the myofibers innervated by it
The major neurotransmitters/neurohormones of the autonomic nervous system are __________.
acetylcholine, epinephrine, and norepinephrine
In the autonomic nervous system, acetylcholine is released by __________.
all preganglionic sympathetic neurons, all preganglionic parasympathetic neurons, and all postganglionic parasympathetic neurons.
Drugs to treat asthma attacks might include __________.
alpha agonists and beta agonists
The disease known as myasthenia gravis produces an unusually rapid onset of fatigue and weakness in certain muscle groups due to __________.
autoimmune destruction of the ACh receptors of motor neurons
Activation of __________ adrenergic receptors raises the concentration of cAMP in effector cells.
beta 1 and beta 2
The autonomic nervous system innervates __________.
cardiac muscle, blood vessels, and adipose tissue
The sympathetic nervous system can exert effects on specific organs via the __________.
collateral ganglia
The disease myasthenia gravis is caused by __________.
destruction of acetylcholine receptors
The widespread effects of the sympathetic nervous system during the fight or flight response throughout the body is due to the fact that __________
each preganglionic neuron synapses with several postganglionic neurons, the catecholamines released from the adrenal glands function as hormones and a given preganglionic neuron may synapse with postganglionic neurons in other ganglia of the sympathetic chain
A toxin that prevents the release of acetylcholine at the neuromuscular junction would cause __________.
flaccid paralysis of skeletal muscles
The somatic nervous system differs from the parasympathetic nervous system in that __________.
it is mostly under voluntary control and the efferent pathway consists of only a single motor neuron
Symptoms of diabetic neuropathy that involve the autonomic nervous system may include __________.
lack of awareness of hypoglycemia urinary incontinence erectile dysfunction
Sympathetic preganglionic neurons emerge from the __________ portion of the spinal cord.
lumbar and thoracic
Somatic motor neurons in the spinal cord control all of the following muscles, except those that __________.
move the face
A toxin that inhibits acetylcholinesterase at the neuromuscular junction would cause __________.
muscle spasms and respiratory failure
Curare produces skeletal muscle paralysis because it is a(n) __________.
nicotinic cholinergic antagonist
Muscarinic receptors are located on __________.
parasympathetic target organs
In contrast to autonomic synapses, the synapses between neurons and skeletal muscle (neuromuscular junctions) __________.
produce end-plate potentials that almost always bring the postsynaptic muscle cell to threshold and almost always produce muscle contractions when the synapse is active, are always excitatory and produce end-plate potentials that almost always bring the postsynaptic muscle cell to threshold
Effector tissue of the somatic motor division is __________.
skeletal muscle
CNS areas that are involved in the control of autonomic functions include the __________.
spinal cord, hypothalamus, and pons
If a somatic motor neuron fires an action potential, then __________.
the response is always excitatory
Synapses between postganglionic neurons and effector organs are different from other synapses in that __________.
there are no distinct postsynaptic sites on the effector organs and transmitter is released from several areas on the postganglionic axon
