Chapter 14, The Autonomic Nervous System

Front 1

What do the motor neurons of the Autonomic Nervous System (ANS) do?

Back 1

Innervate smooth and cardiac muscle and glands
Operate via subconscious control
Involuntary Nervous System

Front 2

What do the majority of the ANS motor neurons effect?

Back 2

Viscera

Front 3

In what three areas does the ANS differ from the Somatic Nervous System (SNS)?

Back 3

Effectors
Efferent pathways
Target organ responses

Front 4

What are the effectors of the SNS?

Back 4

Skeletal muscels

Front 5

What are the 3 specific effectors of the ANS?

Back 5

cardiac muscle, smooth muscle, and glands

Front 6

What do efferent pathways consist of?

Back 6

Heavily myelinated axons of the somatic motor neurons extending from the CNS to the effector (Group A fibers)

Front 7

Describe the two-neuron chain of the ANS

Back 7

The preganglionic (first) neuron has a thin, lightly myelinated axon and is in the brain or spinal cord
The postganglionic (second) neuron extends to an effector organ, it is thinner and contains no myelin

Front 8

All somatic motor neurons release what neurotransmitter, which has what kind of effect?

Back 8

Acetylcholine (ACh)

Excitatory

Front 9

In the ANS, what neurotransmitter(s) do(es) the preganglionic fibers release?

Back 9

Acetylcholine (ACh)

Front 10

In the ANS, what neurotransmitter(s) do(es) postganglionic fibers release. Is the effect stimulatory or inhibitory?

Back 10

Postganglionic fibers release norepinephrine or ACh and the effect is either stimulatory or inhibitory

Front 11

ANS effect on the target organ is dependent upon what two things?

Back 11

the neurotransmitter released and the receptor type of the effector

Front 12

What are the two divisions of the autonomic nervous system?

Back 12

sympathetic and parasympathetic

The two divisions counterbalance each other.

Front 13

What does the sympathetic division of the ANS do?

Back 13

The sympathetic mobilizes the body during extreme situations (fight or flight).

Front 14

What does the parasympathetic division of the ANS do?

Back 14

The parasympathetic performs maintenance activities and conserves body energy

Front 15

What is the parasympathetic division concerned with?

Back 15

keeping body energy use low

Front 16

What three activities does the parasympathetic division involve?

Back 16

Involves the D activities – digestion, defecation, and diuresis

Front 17

Describe the activity of the parasympathetic division in a person who relaxes after a meal.

Back 17

Blood pressure, heart rate, and respiratory rates are low
Gastrointestinal tract activity is high
The skin is warm and the pupils are constricted

Front 18

What activities does the sympathetic division involve?

Back 18

Involves E activities – exercise, excitement, emergency, and embarrassment (lie detector tests monitor the sympathetic reaction)

Front 19

During exercise, the sympathetic division does what?

Back 19

Promotes adjustments during exercise – blood flow to organs is reduced, flow to muscles is increased

Front 20

Describe the sympathetic division's activity in a person who is threatened.

Back 20

Heart rate increases, and breathing is rapid and deep
The skin is cold and sweaty, and the pupils dilate

Front 21

Where do the sympathetic divisions fibers originate?

Back 21

Thoracolumbar region of the spinal cord

Front 22

Describe the length of the sympathetic division's fibers.

Back 22

Short preganglionic and long postganglionic

Front 23

Where are the ganglia of the sympathetic division located?

Back 23

close to the spinal cord

Front 24

Where do the parasympathetic divisions fibers originate?

Back 24

brain and sacral spinal cord

Front 25

Describe the length of the parasympathetic division's fibers.

Back 25

Long preganglionic and short postganglionic

Front 26

Where are the ganglia of the parasympathetic division located?

Back 26

In the visceral effector organs

Front 27

Sympathetic Outflow

Where does the sympathetic outflow arise from?

Back 27

Arises from spinal cord segments T1 through L2

Front 28

Sympathetic Outflow

Where are the sympathetic neurons located in the spinal cord?

Back 28

in the lateral horns

Front 29

Sympathetic Outflow

Which kind of fibers innervate the numerous organs of the body?

Back 29

Postganglionic

Front 30

Parasympathetic Outflow: Cranial

What cranial nerve effects the eye

Back 30

Occulomotor (III)

Front 31

Parasympathetic Outflow: Cranial

What Cranial nerve effects the Salivary, nasal, and lacrimal glands?

Back 31

Facial (VII)

Front 32

Parasympathetic Outflow: Cranial

What Cranial nerve effects the Parotid salivary glands

Back 32

Glossopharyngeal (IX)

Front 33

Parasympathetic Outflow: Cranial

What Cranial nerve effects the Heart, lungs, and most visceral organs

Back 33

Vagus (X)

Front 34

Parasympathetic Outflow: Sacral

What Cranial nerve effects the Large intestine, urinary bladder, ureters, and reproductive organs

Back 34

S2-S4

Front 35

What three things do the fibers in the pathway to the head do?

Back 35

Serve the skin and blood vessels of the head
Stimulate dilator muscles of the iris
Inhibit nasal and salivary glands

Front 36

What do the preganglionic fibers in the pathways to the thorax innervate?

Back 36

These fibers innervate the heart via the cardiac plexus, as well as innervating the thyroid and the skin

Front 37

What do the postganglionic fibers in the pathways to the thorax do?

Back 37

Postganglionic fibers directly serve the heart, aorta, lungs, and esophagus

Front 38

What five organs do the postganglionic fibers in the pathways to the abdomen innervate?

Back 38

Postganglionic fibers serve the stomach, intestines, liver, spleen, and kidneys

Front 39

What three organs do the postganglionic fibers in the pathways to the pelvis innervate?

Back 39

Postganglionic fibers serve the distal half of the large intestine, the urinary bladder, and the reproductive organs

Front 40

What type of pathways do visceral reflexes always contain?

Back 40

Polysynaptic

Front 41

Where are the afferent fibers of visceral reflexes found?

Back 41

in spinal and autonomic nerves

Front 42

Identify the receptor, the sensory neuron, the integration center, the motor neurons (both pre and post ganglionic) and the visceral effector

Back 42

Front 43

Describe referred Pain

Back 43

Pain stimuli arising from the viscera are perceived as somatic in origin

Front 44

What may be the cause of referred pain?

Back 44

may be due to the fact that visceral pain afferents travel along the same pathways as somatic pain fibers

Front 45

What are the two major neurotransmitters of the Autonomic Nervous System?

Back 45

Acetylcholine (ACh) and norepinephrine (NE) are the two major neurotransmitters of the ANS

Front 46

In the ANS, ACh is released by all ___________ axons.

Back 46

preganglionic

Front 47

In the ANS, the only postganglionic axons that release ACh are in the __________ division.

Back 47

parasympathetic

Front 48

What are cholinergic fibers?

Back 48

ACh-releasing fibers

Front 49

What are adrenergic fibers

Back 49

sympathetic postganglionic axons that release NE

Front 50

What determines whether a neurotransmitter effect in the ANS is excitatory or inhibitory?

Back 50

The receptor type.

Front 51

In the ANS, what are the two types of receptors that bind ACh?

What are they named for?

Back 51

nicotinic and muscarinic

These are named after drugs that bind to them and mimic ACh effects

Front 52

Where are the three places that nicotinic receptors are found?

Back 52

1.Motor end plates (somatic targets/motor junctions)
2.All ganglionic neurons of both sympathetic and parasympathetic divisions
3.The hormone-producing cells of the adrenal medulla

Front 53

The effect of ACh binding to nicotinic receptors is always _________.

Back 53

stimulatory

Front 54

Where are muscarinic receptors found?

Back 54

Muscarinic receptors occur on all effector cells stimulated by postganglionic cholinergic fibers

Front 55

The effect of ACh binding to muscarinic receptors is:

Back 55

Either inhibitory or excitatory depending on the receptor type of the target organ.

Front 56

What are the two types of adrenergic receptors?

Back 56

alpha and beta

Front 57

effects of norepinephrine binding to:
alpha receptors is generally _____________.
beta receptors is generally _____________.

Back 57

stimulatory

inhibitory