chapter 15 The Autonomic Nervous System

Question 1

Cholinergic neurons release acetylcholine and adrenergic neurons release norepinephrine and epinephrine
True
False

Answer 1

True

Question 2

Because of the location of the preganglionic cell bodies, the sympathetic division of the ANS is also called the craniosacral division; the parasympathetic division is also called the thoracolumbar division.
True
False

Answer 2

False

Question 3

The vagus nerves transmit 80% of the outflow of the parasympathetic preganglionic axons.
True
False

Answer 3

True

Question 4

Organs that receive both sympathetic and parasympathetic motor impulses are said to have dual innervation.
True
False

Answer 4

True

Question 5

Which of the following statements is false?
A single sympathetic preganglionic fiber may synapse with 20 or more postganglionic fibers, which partly explains why sympathetic responses are widespread throughout the body.

Parasympathetic effects tend to be localized because parasympathetic neurons usually synapse in the terminal ganglia with only four or five postsynaptic neurons (all of which supply a single effector).

Some sympathetic preganglionic neurons extend to and terminate in the adrenal medullae.

The parasympathetic preganglionic neurons synapse with the postganglionic axons in the prevertebral ganglia.

Parasympathetic preganglionic neurons emerge from the CNS as part of a cranial nerve or anterior root of a spinal nerve.

Answer 5

The parasympathetic preganglionic neurons synapse with the postganglionic axons in the prevertebral ganglia.

Question 6

Which autonomic plexus supplies the large intestine?

1. Renal
2. Inferior mesenteric
3. Hypogastric
4. Superior mesenteric
5. Celiac

2, 3, and 4

1, 2, 3, 4, and 5

3 and 4

4 and 5

2 and 4

Answer 6

2 and 4

Question 7

Which of the following statements are true?

1. The somatic nervous system and the ANS both include sensory and motor neurons.
2. Somatic motor neurons release the neurotransmitter norepinephrine.
3. The effect of an autonomic motor neuron is either excitation or inhibition, but that of a somatic motor neuron is always excitation.
4. Autonomic sensory neurons are mostly associated with interoceptors.
5. Autonomic motor pathways consist of two motor neurons in series.
6. Somatic motor pathways consist of two motor neurons in series.

1, 2, 3, 4, and 5

1, 3, 4, and 5

2, 3, 5, and 6

1, 3, 5, and 6

2, 4, 5, and 6

Answer 7

1, 3, 4, and 5

Question 8

Which of the following statements is false?

The first neuron in an autonomic pathway is the preganglionic neuron.

The axons of preganglionic neurons are located in spinal or cranial nerves.

The postganglionic neuron’s cell body is within the CNS.

Postganglionic neurons relay impulses from autonomic ganglia to visceral effectors.

All somatic motor neurons release acetylcholine.

Answer 8

The postganglionic neuron’s cell body is within the CNS.

Question 9

Which of the following is true?

1. Monoamine oxidase enzymatically breaks down norepinephrine.
2. Activation of α2 and β2 receptors generally produces excitation in the effectors.
3. A beta blocker works by preventing activation of β receptors by epinephrine and norepinephrine.
4. An agonist is a substance that binds to a receptor and prevents the natural neurotransmitter from exerting its effect.
5. Activation of nicotinic receptors always causes excitation of the postsynaptic cell.

2 and 3
1, 2, and 3
2, 4, and 5
1, 2, 3, 4, and 5
1, 3, and 5

Answer 9

1, 3, and 5

Question 10

Which of the following are cholinergic neurons?

1. All sympathetic preganglionic neurons
2. All parasympathetic preganglionic neurons
3. All parasympathetic postganglionic neurons
4. All sympathetic postganglionic neurons
5. Some sympathetic postganglionic neurons

1, 2, 3, and 5
1, 2, 3, and 4
2, 3, and 5
2 and 5
1, 3, and 5

Answer 10

1, 2, 3, and 5

Question 11

Which of the following statements are true?
1. Most sympathetic postganglionic axons are adrenergic.
2. Cholinergic receptors are classified as nicotinic and muscarinic.
3. Adrenergic receptors are classified as alpha and beta.
4. Muscarinic receptors are present on all effectors innervated by parasympathetic postganglionic axons.
5. In general, norepinephrine stimulates alpha receptors more vigorously than beta receptors; epinephrine is a potent stimulator of both alpha and beta receptors.
1, 2, 3, 4, and 5

2, 3, 4 and 5

1, 3, 4, and 5

3, 4, and 5

1, 2, 3, and 4

Answer 11

1, 2, 3, 4, and 5

Question 12

Which of the following are reasons why the effects of sympathetic stimulation are longer lasting and more widespread than those of parasympathetic stimulation?

1. There is greater divergence of sympathetic postganglionic fibers.
2. There is less divergence of sympathetic postganglionic fibers.
3. Acetylcholinesterase quickly inactivates ACh, but norepinephrine lingers in the synaptic cleft for a longer time.
4. Norepinephrine and epinephrine secreted into the blood by the adrenal medullae intensify the actions of the sympathetic division.
5. ACh remains in the synaptic cleft until norepinephrine is produced.

1 and 3
1, 3, and 5
1, 3, and 4
2, 3, and 4
2, 3, and 5

Answer 12

1, 3, and 4

Question 13

In an autonomic reflex arc, the preganglionic neuron carries impulses to the autonomic ganglion, while the postganglionic neuron carries impulses from the autonomic ganglion to the effectors.
True
False

Answer 13

True

Question 14

The gray matter communicantes are myelinated preganglionic fibers that connect the anterior rami of spinal nerves with the ganglia of the sympathetic trunk.
True
False

Answer 14

False

Question 15

Increased activity of the parasympathetic system is controlled by the posterior and lateral portions of the hypothalamus.
True
False

Answer 15

False

Question 16

All of the following would be indicators of increased sympathetic activity EXCEPT:
Dilated pupils
Increased blood flow to skeletal muscles
Constricted bronchioles
Decreased blood flow to digestive viscera

Answer 16

Constricted bronchioles