Question 1

The motor pathway of the autonomic nervous system usually involves __________ neurons.

Accepted Answer

The motor pathway of the autonomic nervous system usually involves two neurons: a preganglionic neuron and a postganglionic neuron. The preganglionic neuron originates in the central nervous system and synapses with the postganglionic neuron in a ganglion outside of the central nervous system. The postganglionic neuron then innervates the target organ.

Question 2

Which of the following is not a feature of the sympathetic division of the ANS?

Accepted Answer

The sympathetic division of the autonomic nervous system (ANS) is characterized by short preganglionic fibers and long postganglionic fibers, not long preganglionic fibers as stated in option C.

Question 3

Sympathetic fibers arise only from the __________ region(s)of the spinal cord.

Accepted Answer

Sympathetic fibers arise from the thoracic and lumbar regions of the spinal cord, known as the thoracolumbar region. This region includes the sympathetic chain ganglia, which contain cell bodies of sympathetic neurons. The cervical region contains the cell bodies of sympathetic neurons that innervate structures in the head and neck. The lumbar region innervates structures in the lower limbs. Therefore, the correct answer is B.

Question 4

Preganglionic fibers of the autonomic efferent pathway are _________ and secrete __________.

Accepted Answer

Preganglionic fibers of the autonomic nervous system are myelinated and secrete acetylcholine (ACh) as their neurotransmitter.

Question 5

Most fibers of the parasympathetic nervous system travel in the __________.

Accepted Answer

The vagus nerve contains the majority of parasympathetic fibers in the body and innervates organs in the thorax and abdomen.

Question 6

Which of the following is true regarding the autonomic nervous system?

Accepted Answer

Denervation (loss of nerve supply) of the autonomic nervous system would cause hypersensitivity because the body will not be able to regulate the function of the organs that the autonomic nervous system controls, leading to abnormal responses to stimuli. A, B, C, and E are all incorrect statements about the autonomic nervous system.

Question 7

The sympathetic chain of ganglia is found at the __________ levels of the spinal cord.

Accepted Answer

The sympathetic chain of ganglia, also known as the sympathetic trunk, extends along the entire length of the spinal column, from the cervical level down to the coccygeal level, encompassing cervical, thoracic, lumbar, sacral, and coccygeal regions. This allows it to influence a wide range of bodily functions through its connections to various organs and tissues.

Question 8

Preganglionic fibers run from the _________ to the __________.

Accepted Answer

Preganglionic fibers originate in the central nervous system's gray matter and extend to the autonomic ganglia, where they synapse with postganglionic neurons that innervate target organs.

Question 9

Which of the following structures releases neurotransmitter molecules in a paravertebral ganglion?

Accepted Answer

Preganglionic sympathetic fibers release neurotransmitters at the synapse with the postganglionic neuron in the paravertebral ganglion, which is part of the sympathetic nervous system.

Question 10

The neurotransmitter(s)associated with autonomic ganglia is(are)__________.

Accepted Answer

The neurotransmitter associated with autonomic ganglia is acetylcholine (ACh).

Question 11

The solar plexus is used as a name for the __________.

Accepted Answer

The solar plexus refers to the network of nerves located in the abdominal region, specifically the celiac and mesenteric ganglia, which are part of the sympathetic nerve route responsible for regulating various digestive and hormonal functions. Options A, B, and D are not accurate descriptions of the solar plexus.

Question 12

The background rate of sympathetic and parasympathetic activity is called ___________.

Accepted Answer

The background rate of sympathetic and parasympathetic activity is called autonomic tone. The other options are either more specific (such as "fight-or-flight" activity referring only to the sympathetic response) or more broad (such as "visceral motor activity" referring to any motor activity in the viscera, not just autonomic activity). Autonomic reflex arc activity is also more specific and refers to the reflexive response in the autonomic nervous system.

Question 13

The effect of autonomic fibers on target cells is _________.The effect of somatic fibers on target cells is __________.

Accepted Answer

The autonomic nervous system can either excite or inhibit its target cells depending on the type of neurotransmitter released and the receptors present on the target cells. In contrast, the somatic nervous system, which controls skeletal muscles, is always excitatory because it uses acetylcholine as its neurotransmitter, which always excites skeletal muscle cells.

Question 14

The adrenal medulla secretes mostly ___________.

Accepted Answer

The adrenal medulla is known to secrete mainly epinephrine (adrenaline) during the fight-or-flight response. While norepinephrine is also secreted, it is released primarily by the sympathetic nervous system rather than the adrenal medulla. The other choices, dopamine, endorphins, and acetylcholine, are not typically secreted by the adrenal medulla.

Question 15

The parasympathetic division arises from the __________ regions of the spinal cord.

Accepted Answer

The parasympathetic division of the autonomic nervous system primarily arises from the brainstem and the sacral region of the spinal cord. This system is responsible for "rest and digest" functions, contrasting with the "fight or flight" functions of the sympathetic division.

Question 16

Which of the following structures is not associated with the autonomic nervous system?

Accepted Answer

The answer of Which of the following structures is not...

Question 17

Most preganglionic fibers in the sympathetic nervous system synapse with __________.

Accepted Answer

Most preganglionic fibers in the sympathetic nervous system synapse with 10-20 postganglionic neurons located in sympathetic ganglia.

Question 18

Which of the following is not a reason that somatic reflexes act faster than visceral reflexes?

Accepted Answer

The distance of effector organs from the spinal cord does not significantly affect the speed of reflexes. The speed difference between somatic and visceral reflexes is primarily due to factors like myelination, the number of neurons involved, and the number of chemical synapses, rather than the physical distance of the effector organs from the spinal cord.

Question 19

In response to high blood pressure,stretch receptors called __________ in the walls of arteries carrying blood to the head,will trigger a reflex that causes the heart to __________ its beats per minute.

Accepted Answer

Baroreceptors in the walls of arteries detect changes in blood pressure and can trigger a reflex to decrease the heart rate in response to high blood pressure, helping to bring the pressure back to normal levels.

Question 20

Which of the following is not a characteristic of the parasympathetic division of the ANS?

Accepted Answer

The parasympathetic division of the autonomic nervous system (ANS) is characterized by long preganglionic fibers and short postganglionic fibers, which is the opposite of what is stated in option D.

Quiz 15: The Autonomic Nervous System and Visceral Reflexes