Exam 2: ANS

Question 1

Autonomic nervous system is synonymous with:

Answer 1

visceral motor system

Question 2

Do dermatome nerves in the trunk form plexi?

Answer 2

No, only in the upper/lower limb

Question 3

Where do fibers go in the sympathetic nervous system?

Answer 3

Everywhere

Question 4

Where do fibers NOT go in the parasympathetic nervous system?

Answer 4

They do not go to the body wall or the limbs

Question 5

Function of the ANS?

Answer 5

Transmit signals to smooth muscle and glands

Question 6

Which two systems make up the ANS?

Answer 6

Sympathetic and parasympathetic

Question 7

What are end organ examples for ANS?

Answer 7

Smooth muscle, glands, modified cardiac muscle, SA and AV nodes of the head

Question 8

Are major organs innervated by both parasympathetic and sympathetic or just one?

Answer 8

Both, they have dual motor control

Question 9

Are simple structures innervated by both parasympathetic and sympathetic or just one?

Answer 9

Only sympathetic

Question 10

Where are preganglionic neurons (presynaptic neurons) located?

Answer 10

Cell body within grey matter of CNS

Question 11

Do preganglionic neurons synapse?

Answer 11

Yes

Question 12

Where are postganglionic neurons located?

Answer 12

Cell bodies outside the CNS and make up the automatic ganglia

Question 13

Where does the postganglionic neuron terminate?

Answer 13

On target (end) organ

Question 14

Where do preganglionic neurons terminate?

Answer 14

Within an autonomic ganglia upon the cells body of a postganglionic neuron

Question 15

Where is the parasympathetic system not located?

Answer 15

Cervical spinal cord

Question 16

Where in the brain is the parasympathetic system located?

Answer 16

Craniosacral: brainstem (cranial nerve nuclei), S2-S4 spinal cord (lateral horn)

Question 17

Where is the sympathetic system located?

Answer 17

Thoracolumbar (T1-L2 spinal cord lateral horn)

Question 18

How many visceral motor (autonomIc) ganglia exist and what are they?

Answer 18

3; paravertebral ganglia, prevertebral ganglia, and intrmural ganglia

Question 19

Which system are the paravertebral ganglia used for?

Answer 19

Only for the sympathetic system

Question 20

What do the paravertebral ganglia innervate?

Answer 20

Smooth muscle (arteries), and glands in the body wall/limbs, thoracic cavity viscera, and head

Question 21

Where do the prevertebral ganglia lie?

Answer 21

Anterior to the vertebral column, close to major abdominal arteries

Question 22

Which system are the prevertebral ganglia used for?

Answer 22

Only for the sympathetic system

Question 23

What do the prevertebral ganglia directly innervate?

Answer 23

Abdominal cavity structures + organs, pelvic cavity structures + organs

Question 24

Where is the intramural ganglia (terminal ganglia) located?

Answer 24

Located close to or within the wall
of the effector organ

Question 25

Which system are the intramural ganglia used for?

Answer 25

Used only for parasympathetic system

Question 26

Which structures do the intramural ganglia innervate?

Answer 26

Structures + organs in thorax, abdomen, and pelvic cavities

Question 27

What does the hypothalamus (part of the CNS) do for the ANS?

Answer 27

Sends descending fibers directly to preganglionic sympathetic or parasympathetic cell bodies * Lateral horn of T1 – L2 (3) * Specific cranial nerve nuclei in the brainstem * Lateral horn of S2 – S4

Question 28

Which higher-order brain regions does the hypothalamus communicate with?

Answer 28

Communicates with other higher- order brain regions: * Insular cortex (insula) * Limbic system

Question 29

What do preganglionic sympathetic cell bodies form?

Answer 29

Form a column of cells extending the length of the thoracic and upper lumbar portions of the spinal cord -T1 – L2(L3) --thoracolumbar

Question 30

Where is the ONLY place preganglionic sympathetic cell bodies exist?

Answer 30

Intermediolateral cell column (IML): T1 - L2 (L3)

Question 31

What are the 3 locations where preganglionic sympathetic cell bodies are located?

Answer 31

Head: T1 – T6 Upper Limb: T1 – T6 Thoracic cavity viscera: T1 – T

Question 32

If sympathetic innervation needs to reach all regions of the body and head but is restricted to T-L2 of the spinal cord, how does it do this?

Answer 32

Pathways that take different routes

Question 33

Are the beginnings of all pathways the same?

Answer 33

Yes

Question 34

How do preganglionic sympathetic fibers exit the CNS?

Answer 34

Via anterior (ventral) roots -MOTOR

Question 35

Do preganglionic sympathetic fibers become components of the spinal nerve?

Answer 35

Yes, but only briefly since the spinal nerve only hits body wall + U/L limbs

Question 36

Where do preganglionic sympathetic fibers exit the spinal nerve?

Answer 36

Proximal to the branching point of the ventral/dorsal rami via white ramus communication

Question 37

Which branch is the only branch for communication between preganglionic sympathetic fibers and the sympathetic trunk?

Answer 37

Spinal nerves T1-L2 (L3)

Question 38

What is the sympathetic trunk composed of?

Answer 38

Paravertebral ganglia

Question 39

What is the sympathetic trunk?

Answer 39

Paired structure lying on either side (right & left) of the vertebral column

Question 40

What is the function of the sympathetic trunk?

Answer 40

Distributes postganglionic sympathetic innervation throughout the body

Question 41

Where is the location where the sympathetic trunk runs?

Answer 41

Runs the entire length of the vertebral column: (C1 – coccyx)

Question 42

What happens when preganglionic sympathetic fibers reach the sympathetic trunk?

Answer 42

They can take 1 of 4 routes depending on where in the body their final target is

Question 43

List route #1 a preganglionic sympathetic fiber can take after entering into the sympathetic trunk:

Answer 43

Synapse at the same level they entered: *Target is in the body wall of T1 – L2 (3) *Target is in the thoracic cavity or thoracoabdominal (trunk) body wall

Question 44

List route #2 a preganglionic sympathetic fiber can take after entering into the sympathetic trunk:

Answer 44

Ascend in the sympathetic trunk & then synapse: *Target is in the body wall superior to T1 (primarily upper limb & neck) *Target is in the head

Question 45

List route #3 a preganglionic sympathetic fiber can take after entering into the sympathetic trunk:

Answer 45

Descend in the sympathetic trunk & then synapse: *Target is in the body wall inferior to L2(3) (primarily lower limbs)

Question 46

List route #4 a preganglionic sympathetic fiber can take after entering into the sympathetic trunk:

Answer 46

Leave the sympathetic trunk without synapsing: *Target is in the abdominal cavity *Target is in the pelvic cavity

Question 47

What happens to the fibers if the preganglionic sympathetic fibers choose route #1 (body wall of T1-L2(3) or viscera in the thoracic cavity)?

Answer 47

They synapse with a postganglionic cell body within a paravertebral ganglion of the sympathetic trunk at the SAME level it entered the sympathetic trunk

Question 48

What happens to the fibers if the preganglionic sympathetic fibers choose route #2 (target superior to T1)?

Answer 48

They ascend within the sympathetic trunk to synapse with a postganglionic cell body located in a paravertebral ganglion in the cervical region (C1 – C8)

Question 49

What happens to the fibers if the preganglionic sympathetic fibers choose route #3 (inferior to L2 (L3))?

Answer 49

They descend within the sympathetic trunk to synapse with a postganglionic cell body located in a paravertebral ganglion in the lower lumbar or sacral region

Question 50

What happens to the fibers if the preganglionic sympathetic fibers choose route #4 (leave the trunk w/o synapsing)?

Answer 50

The nerve is then called a thoracic or lumbar splanchnic nerve

Question 51

What does the thoracic/lumbar nerve refer to?

Answer 51

Refers to the level of the IML that their cell bodies are located (not where their target is located)

Question 52

Where do the thoracic/lumbar nerves synapse?

Answer 52

Prevertebral ganglion

Question 53

Where do splanchnic nerves go?

Answer 53

To viscera in a cavity (thoracic, abdominal, or pelvic)

Question 54

Does splanchnic tell you if it's pre/post ganglionic?

Answer 54

No

Question 55

Does splanchnic tell you if it is sympathetic or parasympathetic?

Answer 55

No

Question 56

Where is cardiopulmonary splanchnic nerve going to?

Answer 56

Postganglionic sympathetic to thoracic cavity viscera

Question 57

Where is thoracic + lumbar splanchnic nerve going?

Answer 57

Preganglionic sympathetic to abdominal & pelvic cavity viscera

Question 58

Where is the pelvic splanchnic nerve going?

Answer 58

Preganglionic parasympathetic distal large intestine & pelvic cavity viscera