Physiology Ch. 11
Which functions are controlled through the autonomic nervous system? 1. blood pressure 2. heart rate 3. water balance 4. temperature regulation
1, 2, 3, 4
What stimulates ACh release into the synaptic cleft of a neuromuscular junction?
An action potential opens voltage-gated Ca2+ channels in the axon terminal.
The binding of acetylcholine to muscarinic receptors causes __________.
G protein activation
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.
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
Which of the following is an example of antagonistic control?
Parasympathetic stimulation causes bronchoconstriction, while sympathetic stimulation causes bronchodilation. Submit
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 statements is true?
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.
During strenuous exercise, which of the following are likely to be more active?
Sympathetic nervous system and somatic nervous system
A patient was exposed to a nerve gas during a chemical warfare attack. The nerve gas inhibited the enzyme acetylcholinesterase. What will happen to the amount of acetylcholine in the synaptic cleft, and how can this be treated?
The amount of acetylcholine will increase; treat with a cholinergic receptor antagonist. Submit
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.
Epinephrine and norepinephrine that are released from the adrenal glands affect target tissue for a longer period of time than the same substances released from neurons at their peripheral receptors. Why?
There are no enzymes to break down epinephrine and norepinephrine in the blood and very little in peripheral tissues.
Which of the following is NOT a similarity between somatic motor and autonomic pathways?
They all stimulate muscarinic receptors
End-plate potentials at the neuromuscular junction are similar to excitatory postsynaptic potentials in which of the following way(s)?
They are depolarizing
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 ACh receptors clustered at the top of each fold.
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
sympathetic tissue receptor
adrenergic receptor
In contrast to autonomic synapses, the synapses between neurons and skeletal muscle (neuromuscular junctions) __________.
all answers are correct
Motion sickness is probably caused by miscommunication between which of the following systems?
all answers are correct
Symptoms of diabetic neuropathy that involve the autonomic nervous system may include __________.
all answers are correct
The autonomic nervous system is involved in which of the following actions?
all answers are correct
The widespread effects of the sympathetic nervous system during the fight or flight response throughout the body is due to the fact that __________.
all answers are correct
Which of the following organs is/are controlled by both the sympathetic and parasympathetic branches of the autonomic nervous system?
all answers are correct
Which of the following statements about the autonomic nervous system is(are) true?
all answers are correct
Which of the following statements about the activation of adrenergic receptors in the sympathetic nervous system are true?
all answers are incorrect
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
The presence of two peripheral efferent neurons in a pathway is typical of the ________ division.
autonomic
Which of the following best describes the direction and function of efferent signals?
away from the central nervous system, cause motor effects in glands or muscles
Autonomic neurotransmitters are synthesized in the ________.
axon
Activation of __________ adrenergic receptors raises the concentration of cAMP in effector cells.
beta 1 and beta 2
A child is rushed to the hospital after taking one of his grandmother's blood pressure medications. He has a low blood pressure and is also having trouble breathing, with audible wheezing upon exhalation. Which class of drugs did the child most likely take?
beta blocker
The autonomic nervous system innervates __________.
cardiac muscle, blood vessels, and adipose tissue
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 sympathetic nervous system can exert effects on specific organs via the __________.
collateral ganglia
The disease myasthenia gravis is caused by __________.
destruction of acetylcholine receptors
A toxin that prevents the release of acetylcholine at the neuromuscular junction would cause __________.
flaccid paralysis of skeletal muscles
Which of the following is/are targets of the efferent nervous system?
glands, cardiac muscle, skeletal muscle, smooth muscle
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
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
What type of drug would decrease heart rate?
muscarinic agonist
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
Which of the following cell types or structures can be found in both the sympathetic and the parasympathetic nervous system?
preganglionic neurons and chain ganglia
Effector tissue of the somatic motor division is __________.
skeletal muscle
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
CNS areas that are involved in the control of autonomic functions include the __________.
spinal cord, hypothalamus, and pons
blocks sweating
sympathetic antagonist
Which of the following are components of the efferent nervous system?
sympathetic neurons, somatic motor neurons, parasympathetic neurons
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
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
Inside the ganglia are interneurons, which modulate messages.
true for both divisions