ANS

Question 1

The ANS consists of motor neurons that:

Answer 1

Innervate smooth and cardiac muscle and 
glands
Make adjustments to ensure optimal support 
for body activities
Operate via subconscious control

Question 2

Somatic and Autonomic Nervous
Systems

The two systems differ in

Answer 2

1. Effectors
2. Efferent pathways (and their
   neurotransmitters)
3. Target organ responses to
   neurotransmitters

Question 3

Somatic nervous system = Skeletal 
muscles ONLY
ANS =   a. Cardiac muscle
b. Smooth muscle
c. Glands

What are they?

Answer 3

Effectors

Question 4

Somatic nervous system = one thick,
heavily myelinated somatic motor fiber
makes up each pathway from the CNS to
the muscle

Answer 4

Efferent Pathways

Question 5

ANS pathway is a two-neuron chain
1.Preganglionic neuron (in CNS) has a 
thin, lightly myelinated preganglionic 
axon
2.Postganglionic neuron in autonomic 
ganglion has an unmyelinated

Answer 5

Efferent Pathways

Question 6

Somatic nervous system = All somatic motor
neurons release acetylcholine (ACh)
Effects are always stimulatory!!

Answer 6

Neurotransmitter Effects

Question 7

ANS
Preganglionic fibers release ACh
Postganglionic fibers release 
norepinephrine or ACh at effectors
Effect is either stimulatory or inhibitory, 
depending on type of receptors

Answer 7

Neurotransmitter Effects

Question 8

2
Preganglionic = Ach
Postganglionic =
Ach & NE

Answer 8

ANS (Motor neurons)

Question 9

Somatic (Motor Neurons)

Answer 9

1

Ach only

Question 10

ANS (Effectors smooth & cardiac muscle glands)

Answer 10

Smooth & Cardiac

muscle; Glands

Question 11

Somatic (Effector)

Answer 11

Skeletal muscle

Question 12

PARASYMPATHETIC

Nerves emerge from _____
region of brain or spinal cord

Answer 12

craniosacral

Question 13

PARASYMPATHETIC
___preganglionic fibers (synapse
close to or within target organ)
__- postganglionic fibers

Answer 13

long

short

Question 14

PARASYMPATHETIC

neurotransmitters =

Answer 14

ACh only

Question 15

Parasympathetic

____ effect

Answer 15

localized

Question 16

physiological effects = ______
____ = increases salivation,
lacrimation, urination, defecation and digestion

Answer 16

“rest and digest”;

“SLUDD”

Question 17

3 things/structures it decreases = ___

rate, airways (constriction) and pupils (restriction)

Answer 17

heart

Question 17

3 things/structures it decreases = ___

rate, airways (constriction) and pupils (restriction)

Answer 17

heart

Question 18

Cranial Part of Parasympathetic

Division:

Answer 18

CN’s 3, 7, 9 & 10

Question 19

 Serves pelvic organs and distal half of large
intestine
 From neurons in lateral gray matter / horns of
S2-S4
 Axons travel in ventral root of spinal nerves
 Synapse with
 Ganglia in pelvic floor
 Intramural ganglia in walls of distal half of large
intestine, urinary bladder, ureters, and reproductive
organs

Answer 19

Sacral Part of Parasympathetic

Division

Question 20

Sympathetic

nerves emerge from _____ region

Answer 20

thoracolumbar

Question 21

Sympathetic
______ preganglionic fibers (cell bodies in
lateral gray horns)
____postganglionic fibers (cell bodies in
paravertebral chain)

Answer 21

short

long

Question 22

Sympathetic
neurotransmitters
preganglionic = ____________
postganglionic =__________

Answer 22

Ach (just like
Parasympathetic)
NE ** (except sweat
glands = ACh)

Question 23

Some preganglionic fibers pass directly to
the adrenal medulla without synapsing
Upon stimulation, the adrenal medulla
secretes norepinephrine and epinephrine into
the blood

Answer 23

Pathways with Synapses in the Adrenal

Medulla

Question 24

Parasympathetic (Origin)

Answer 24

Craniosacral

Question 25

Sympathetic (Origin)

Answer 25

Thoracolumbar

Question 26

Parasympathetic (Fibers)

Answer 26

LONG Preganglionic SHORT Postganglionic

Question 27

Sympathetic (fibers)

Answer 27

SHORT Preganglionic LONG Postganglionic

Question 28

Parasympathetic (Neurotransmitte | rs)

Answer 28

ACh

Question 29

Sympathetic (Neurotransmitte | rs)

Answer 29

ACh NE

Question 30

Parasympathetic (Distance)

Answer 30

Local Effects

Question 31

Sympathetic (Distance)

Answer 31

Widespread Effects

Question 32

Parasympathetic (Phycological effects)

Answer 32

“Rest and Digest” | “SLUDD”

Question 33

Sympathetic (Physiological | Effects)

Answer 33

“Fight or Flight” | “E’s”

Question 34

All postganglionic neurons (1st synapse area of both sympathetic and parasympathetic) Hormone-producing cells of the adrenal medulla Effect of ACh at nicotinic receptors is always excitatory

Answer 34

Nicotinic Receptors

Question 34

All postganglionic neurons (1st synapse area of both sympathetic and parasympathetic) Hormone-producing cells of the adrenal medulla Effect of ACh at nicotinic receptors is always excitatory

Answer 34

Nicotinic Receptors

Question 35

Found on All effector cells (2nd synapse) stimulated by parasympathetic fibers The effect of ACh at muscarinic receptors Can be either inhibitory or excitatory Depends on the receptor type of the target organ

Answer 35

Muscarinic Receptors

Question 36

generally excitatory: located on virtually all sympathetic organs and radial muscles of the pupil to dilate the pupil, constrict blood vessels to skin, digestive organs; excitatory to constrict visceral organ sphincters

Answer 36

α1 receptors

Question 37

generally inhibitory: inhibit insulin | release from the pancreas.

Answer 37

α2 receptors

Question 38

``` generally excitatory predominately located in the heart to increase heart rate and the kidneys to release Renin (a vasoconstrictor). ```

Answer 38

β1 receptors

Question 39

generally inhibitory: located in the lungs inhibit smooth muscle of bronchioles and thus dilate bronchioles; dilate blood vessels to skeletal muscles and heart, liver to increase blood delivery; relax smooth muscle of gastrointestinal tract and uterus to decrease movement through that tube.

Answer 39

β2 receptors

Question 40

found in the fat cells of the body (thus | thermogenesis) to stimulate lipolysis

Answer 40

β3 receptors

Question 41

controls blood | pressure, even at rest

Answer 41

Sympathetic division

Question 42

Keeps the blood vessels in a continual state of partial constriction(similar to muscle tone)

Answer 42

Sympathetic tone (vasomotor tone)

Question 43

``` Sympathetic fibers fire more rapidly to constrict blood vessels and cause blood pressure to rise Sympathetic fibers fire less rapidly and thus to prompt vessels to dilate to decrease blood pressure ```

Answer 43

Sympathetic Tone

Question 44

``` ______ division normally dominates the heart and smooth muscle of digestive and urinary tract organs Slows the heart Dictates normal activity levels of the digestive and urinary tracts ```

Answer 44

Parasympathetic Tone

Question 45

``` The sympathetic division can override these effects during times of stress Drugs that block parasympathetic responses increase heart rate and block fecal and urinary retention ```

Answer 45

Parasympathetic Tone

Question 45

``` The sympathetic division can override these effects during times of stress Drugs that block parasympathetic responses increase heart rate and block fecal and urinary retention ```

Answer 45

Parasympathetic Tone

Question 46

short- lived, highly localized control over effectors

Answer 46

Parasympathetic division

Question 47

long-lasting, | body wide effects

Answer 47

Sympathetic division

Question 48

= main integrative | center of ANS activity

Answer 48

Hypothalamus

Question 49

``` Subconscious cerebral input via limbic lobe connections influences hypothalamic function Other controls come from the cerebral cortex, the reticular formation, and the spinal cord ```

Answer 49

Control of ANS Functioning