Question 1

Bronchoconstriction brought on by various allergens is a _____ response.

Accepted Answer

Bronchoconstriction brought on by various allergens is a parasympathetic response. Allergic reactions trigger the release of chemical mediators, such as histamine, which activate parasympathetic nerves in the airways, causing bronchoconstriction.

Question 2

Which of the following statements is TRUE for the autonomic nervous system?

Accepted Answer

A) Sensory signals of the autonomic nervous system are not usually consciously perceived.
B) The effect of autonomic motor neurons can be either excitatory or inhibitory.
C) Autonomic motor neurons secrete either acetylcholine or norepinephrine depending on the specific branch of the autonomic nervous system.

Question 3

The neurotransmitter acetylcholine binds with which of the following types of receptors?
1) alpha
2) beta
3) nicotinic
4) muscarinic

Accepted Answer

Acetylcholine binds with two types of receptors: nicotinic and muscarinic. Therefore, the correct choice is 3, 4 only. Alpha and beta receptors are not associated with acetylcholine.

Question 4

Arrange the following components of an autonomic reflex arc in the proper order:
1) preganglionic motor neuron
2) receptor
3) integrating center (interneurons)
4) postganglionic motor neuron
5) visceral effector
6) autonomic ganglion
7) sensory neuron

Accepted Answer

The correct sequence for an autonomic reflex arc starts with the receptor (2) sensing a stimulus, followed by the sensory neuron (7) carrying the signal to the integrating center (3), usually in the central nervous system. From there, the preganglionic motor neuron (1) carries the signal to the autonomic ganglion (6), where it synapses with the postganglionic motor neuron (4), which finally innervates the visceral effector (5).

Question 5

Select the best description of the middle cervical ganglion:

Accepted Answer

The middle cervical ganglion is part of the sympathetic nervous system. It sends impulses along postganglionic axons to the heart, among other targets, helping to regulate heart function.

Question 6

Activation of nicotinic receptors by acetylcholine (ACh) triggers which response in a postsynaptic cell?

Accepted Answer

The answer of Activation of nicotinic receptors by acetylcholine (ACh)...

Question 7

White rami are associated only with thoracic spinal nerves and the first two or three lumbar spinal nerves. Gray rami are associated with all 31 pairs of spinal nerves.

Accepted Answer

Both statements accurately describe the distribution of white and gray rami communicantes in the autonomic nervous system. White rami carry preganglionic sympathetic fibers to the sympathetic chain and are limited to thoracic and upper lumbar nerves, while gray rami, carrying postganglionic fibers, are associated with all spinal nerves.

Question 8

Autonomic plexuses in the thorax, abdomen and pelvis may contain

Accepted Answer

Autonomic plexuses in the thorax, abdomen and pelvis contain sympathetic ganglia, axons of sympathetic and parasympathetic neurons, and axons of autonomic sensory neurons. Therefore, all of the choices are correct.

Question 9

Which of the following responses is a result of sympathetic stimulation?

Accepted Answer

Sympathetic stimulation activates the fight or flight response, which includes increased respiratory rate and depth to provide more oxygen to the body for physical activity. Decreased heart rate and constriction of the pupils would be the result of parasympathetic stimulation, while increased digestive secretions would be the result of both parasympathetic and sympathetic stimulation (although sympathetic stimulation would decrease digestive activity in favor of other functions).

Question 10

Alpha and beta receptors are found in the sympathetic division. They exist on postganglionic neurons and on visceral effectors.

Accepted Answer

The first statement is true, as both alpha and beta receptors are indeed found in the sympathetic division. However, the second statement is false, as alpha and beta receptors are not found on visceral effectors but rather on target tissues such as smooth muscle cells, cardiac muscle cells, and gland cells.

Question 11

Which of the following is/are innervated ONLY by the sympathetic division?
1) arrector pili muscles
2) kidney arterioles
3) sweat glands
4) adipose tissue
5) skeletal muscle arterioles
6) brain arterioles
7) adrenal medulla

Accepted Answer

The answer of Which of the following is/are innervated ONLY...

Question 12

Spinal nerve C4 receives postganglionic sympathetic axons (fibers) from:

Accepted Answer

Gray rami communicantes are responsible for carrying postganglionic sympathetic axons back to the spinal nerves, including C4, allowing for the distribution of sympathetic innervation to the body.

Question 13

Vasoconstriction of peripheral blood vessels is a(n) _____ response.

Accepted Answer

Vasoconstriction of peripheral blood vessels is a response mediated by the sympathetic nervous system, which releases the neurotransmitter norepinephrine at adrenergic receptors on smooth muscle cells in blood vessel walls. Therefore, the correct choice is C) adrenergic. Cholinergic refers to the release of the neurotransmitter acetylcholine, which is involved in parasympathetic nervous system responses. Parasympathetic refers to the division of the autonomic nervous system that opposes the sympathetic division and often has opposite effects on the body. Voluntary refers to actions that are under conscious control, such as movements of the skeletal muscles.

Question 14

The motor neurons of a sympathetic autonomic motor pathway have the following route:
1)gray ramus
2)anterior root of spinal nerve
3)axon collaterals
4)white ramus
5)nerve to a visceral effector
6)sympathetic trunk ganglion

Accepted Answer

The answer of The motor neurons of a sympathetic autonomic...

Question 15

Autonomic neurons that secrete the neurotransmitter acetylcholine:

Accepted Answer

Autonomic neurons that secrete the neurotransmitter acetylcholine include all preganglionic neurons. Postganglionic neurons can secrete either acetylcholine or norepinephrine and are referred to as cholinergic or adrenergic, respectively.

Question 16

Which of the following is NOT a parasympathetic terminal ganglion?

Accepted Answer

The celiac ganglion is a sympathetic ganglion, not a parasympathetic terminal ganglion. The other options (pterygopalatine, otic, submandibular) are all parasympathetic terminal ganglia.

Question 17

Acetylcholine in the autonomic nervous system:

Accepted Answer

Acetylcholine (ACh) in the autonomic nervous system is rapidly broken down by acetylcholinesterase (AChE), which limits its action to a very brief time. This characteristic is in contrast to some other neurotransmitters in the autonomic nervous system that can have longer-lasting effects.

Question 18

Which of the following is NOT part of the sympathetic division?

Accepted Answer

The submandibular ganglion is not part of the sympathetic division. Instead, it is part of the parasympathetic division of the autonomic nervous system. The gray rami, splanchnic nerves, and celiac ganglion are all part of the sympathetic division.

Question 19

Which of the following statements about the autonomic nervous system is FALSE?

Accepted Answer

The motor (output) division of the autonomic nervous system has two divisions, not three: the sympathetic division and the parasympathetic division. The somatic nervous system is not part of the autonomic nervous system; it controls voluntary skeletal muscle movements.

Question 20

Somatic motor neurons synapse with which of the following?

Accepted Answer

Somatic motor neurons innervate and synapse directly with skeletal muscle cells to control voluntary muscle movements. Autonomic ganglia and the adrenal medulla are innervated by autonomic motor neurons, while visceral effectors such as smooth muscles and glands are innervated by autonomic motor neurons as well.

Quiz 19: The Autonomic Nervous System