Autonomic Reflex Arc

Question 1

Preganglionic nerve fibers in the sympathetic nervous system are:

Answer 1

Study on!!!

Question 2

The autonomic nervous system is a complex and well-coordinated network of —– arcs

Answer 2

visceral reflex arcs

Question 3

The autonomic nervous system is a complex and well-coordinated network of visceral reflex arcs that work in concert to maintain whole-body —–.

Answer 3

homeostasis

Question 4

Additionally, these reflex arcs are tightly integrated with the —– system

Answer 4

endocrine system

Question 5

Additionally, these reflex arcs are tightly integrated with the endocrine system. The key points of integration include the —– axis

Answer 5

Renin-Angiotensin-Aldosterone axis

Question 6

Additionally, these reflex arcs are tightly integrated with the endocrine system. The key points of integration include the renin-angiotensin-aldosterone axis as well as regulation of…

Answer 6

antidiuretic hormone,

mineralocorticoids,

glucocorticoids, and

insulin

Question 7

The reflex arc allows for fine adjustments by —– and —– feedback mechanisms

Answer 7

positive and negative feedback mechanisms

Question 8

What are the 5 major components of the Autonomic Reflex Arc?

Answer 8

1. Sensor
2. Afferent pathway
3. Control center
4. Efferent pathway
5. Effector organ

Question 9

*You may want to remember the mnemonic —– to remember the order of afferent and efferent pathways.

Answer 9

“ACE”

(Afferent - Control - Efferent)

Question 10

—– monitor the environment and informs the CNS of changes within the environment

Answer 10

Sensors

Question 11

When a change occurs, the stimulus alters the —– of the sensor.

Answer 11

Electrical potential

Question 12

When a change occurs, the stimulus alters the electrical potential of the sensor. Next, the sensor transduces the stimulus into an —–.

Answer 12

Action potential

Question 13

The —– pathway links the sensor to the control center

Answer 13

Afferent pathway

Question 14

Afferent Pathway conducts the action potential towards the —–.

Answer 14

CNS​

Question 15

Which 3 Control Centers receive the bulk of sensory input from the body?

Answer 15

Hypothalamus, Brainstem, and Spinal cord

Question 16

The cerebral cortex is —— of the autonomic reflex arc per se

Answer 16

Not a component

Question 17

While the cerebral cortex is not a component of the autonomic reflex arc per se, it can modulate autonomic output that may occur with —–.

Answer 17

emotions

Question 18

While the cerebral cortex is not a component of the autonomic reflex arc per se, it can modulate autonomic output that may occur with emotions, such as with —– and —–.

Answer 18

fear and anxiety

Question 19

The —– pathway links the control center to the effector organ

Answer 19

efferent pathway

Question 20

The efferent pathway conducts the —– towards the effector organ

Answer 20

action potential

Question 21

The efferent pathway almost always consists of two nerve fibers:

Answer 21

1 preganglionic nerve, and

1 postganglionic nerve

Question 22

The —– is the site where the preganglionic nerve and the postganglionic nerve form a synapse

Answer 22

ganglion

Question 23

The preganglionic neuron is a —– fiber

Answer 23

myelinated B-fiber

Question 24

The preganglionic neuron exits the CNS and synapses with the —– fiber

Answer 24

postganglionic fiber

Question 25

The preganglionic neuron exits the CNS and synapses with the postganglionic fiber in an —– ganglion

Answer 25

autonomic ganglion

Question 26

The preganglionic neuron releases —–.

Answer 26

acetylcholine

Question 27

The preganglionic neuron releases acetylcholine onto a —– receptor

Answer 27

nicotinic type-N receptor

Question 28

The preganglionic neuron releases acetylcholine onto a nicotinic type-N receptor in the —–.

Answer 28

ganglion

Question 29

The postganglionic neuron is —– fiber

Answer 29

an unmyelinated C-fiber

Question 30

The postganglionic neuron exits the ganglion and innervates the —– organ

Answer 30

effector organ

Question 31

In the PNS, the postganglionic neuron is a —– postganglionic fiber

Answer 31

cholinergic postganglionic fiber

Question 32

In the SNS, the postganglionic neuron is a —– postganglionic fiber

Answer 32

adrenergic postganglionic fiber

Question 33

In the PNS, a cholinergic postganglionic fiber releases —– onto its effector organ

Answer 33

acetylcholine

Question 34

In the SNS, an adrenergic postganglionic fiber releases —– onto its effector organ.

Answer 34

norepinephrine

Question 35

In the PNS, a cholinergic postganglionic fiber releases acetylcholine onto its effector organ.

In the SNS, an adrenergic postganglionic fiber releases norepinephrine onto its effector organ.

What are some exceptions to this rule?

Answer 35

Adrenal medulla, sweat glands,

piloerector muscles, and some blood vessels

Question 36

The Effector Organ elicits a —– change to restore homeostasis

Answer 36

physiologic change

Question 37

Preganglionic nerve fibers in the sympathetic nervous system are:

Answer 37

Correct Answer:

Myelinated B-fibers

Question 38

The efferent limb of the ANS reflex arc consists of 2 nerve fibers. The preganglionic fiber is a —– fiber

Answer 38

myelinated B- fiber

Question 39

The efferent limb of the ANS reflex arc consists of 2 nerve fibers. The postganglionic fiber is a —– fiber

Answer 39

unmyelinated C-fiber

Question 40

References**:

Answer 40

• Barash. Clinical Anesthesia**.* 8th ed.* *201*7. *p. 333-335**.
• Hall.* Guyton and Hall Textbook of Medical Physiology 12th ed. 2013. p. 560 & 729- 7**31.