UNit 6 The Autonomic nervous system

Question 1

What are the components of the peripheral nervous system?

Answer 1

12 pairs of cranical nervees, 31 pairs of spinal nerves, the autonomic nervous sysrwm

Question 2

What are the four major types of fibers found in cranial and spinal nerves?

Answer 2

somatic afferent, somatic efferent, visceral afferent, visceral efferent

Question 3

Where do nerve impulses from somatic afferents come from?

Answer 3

skin, joints, muscles

Question 4

Where are the cell bodies for somatic afferents located?

Answer 4

posterior/dorsal root ganglia, crannial nerve ganglia

Question 5

What is the pathway from a sensory receptor into the spinal cord?

Answer 5

one sensory neuron with body in dorsal root

Question 6

Where is the first cell body found in the viceral efferent system?

Answer 6

intermediate zone of grey matter

Question 6

Where is the second cell body (post ganglionic) neuron found for the visceral efferents?

Answer 6

outside the CNS in an autonomic ganglion

Question 6

What are some commonly innervated structures with visceral efferents?

Answer 6

glands, cardiac muscle, smooth muscle

Question 7

What is the primary goal of the autonomic nervous system?

Answer 7

maintain homeostasis

Question 8

Why are autonomic fibers found all over the body?

Answer 8

they innervate blood vessels that have smooth muscle in their walls, also cardiac muscle, and glands (most parts of the body contain glands of some sort)

Question 9

What are the two divisions of the autonomic nervous system?

Answer 9

sympathetic and parasympathetic

Question 10

Where is the first cell body located in the sympathetic nervous system?

Answer 10

intermediolateral nucleus of lateral grey horn

Question 11

Where do the axons of the sympathetic preganglionic neuron travel to?

Answer 11

leave the nervous system through the anterior or ventral root, enters the spinal nerve through ventral ramus, leaves ventral ramus to travel to the white communicating ramus where it connects to the sympathetic trunk

Question 12

Where is the only place you find the preganglionic axons of the sympathetic nervous system?

Answer 12

white communicating rami

Question 13

Where is the postganglionic neuron of the sympathetic nervous system found?

Answer 13

sympathetic trunk

Question 14

Where is the sympathetic trunk located?

Answer 14

21-23 cell bodies located bilaterally along the vertebral bodies, they are linked together by other nerve fibers

Question 15

Where does the sympathetic trunk extend from?

Answer 15

base of skull to coccyx

Question 16

What is it called where the two sympathetic trunks join one another?

Answer 16

ganglion impar

Question 17

Where might the axons of the preganglionic neurons synapse upon after entering the sympathetic trunk?

Answer 17

on a postganglionic sympathetic neuron at the same level as they entered, ascend to a higher level ganglion (true usually in thoracic region), descend to a lower neuron (true usually lumbar region), or they may pass through the trunk into a splanchnic nerve to synapse on a collateral ganglion located in the abdominal region

Question 18

What are the collateral ganglion typically associated with?

Answer 18

large vessels of the abdominal aorta

Question 19

Where are the postganglion axon fibers typically located?

Answer 19

exit sympathetic trunk via the gray comminicating rami to the anterior ventral ramus of the spinal nerve

Question 20

where do the sympathetic post ganglionic fibers travel after they reach the spinal nerve?

Answer 20

distributed through the body to structures in the skin such as sweat glands, smooth muscles in blood vessels, erector pili muscles of limbs and body wall

Question 21

What is the consequence of all parts of the body having blood vessels and glands?

Answer 21

all spinal nerves must receive a gray ramus with sympathetic nerve fibers

Question 22

What is another possible course for the post ganglionic nerve fibers?

Answer 22

can leave the sympathetic trunk as viceral branches that travel directly to their effector organ

Question 23

What is the last possibility for postganglionic sympathetic nerve fibers?

Answer 23

they can leave the uppermost chain ganglion (superior cervical ganglion) most of which will run along the internal and external carotid plexuses to supply structures in the head

Question 24

How do the postganglionic sympathetic nerve fibers of the

collateral ganglia run?

Answer 24

they exit the ganglion via two routes: form plexuses around single large bands of the aorta and follow the vessel, or they may leave as visceral branches that enter into hypogastric nerves to innervate the organs of the abdominal region

Question 25

What are a few actions of the sympathetic system?

Answer 25

increases heart rate and force of the contraction, dilates arterioles of the heart and limb muscles, constricts blood vessels in certain circulations, inhibits digestive glands, dilates the pupil

Question 26

What nerves are the preganglionic neurons of the parasympathetic nervous system associated with?

Answer 26

cranial-> CN3,7,9,10

oculomotor, facial nerve, glossopharyngeal, vagus

Sacral–>S2, 3, 4

Question 27

Where are the cell bodies for the oculomotor nerve located?

Answer 27

Edwinger-Westphal Nucleus in the midbrain

Question 28

Where are the cell bodies for the facial nerve located?

Answer 28

superior salivatory nucleus of the medulla

Question 29

Where are the cell bodies for the glossopharyngeal nerves located?

Answer 29

inferior salivatory nucleus of the medulla

Question 30

Where are the cell bodies of the vagus nerve located?

Answer 30

dorsal vagal nucleus of the medulla

Question 31

Where are the cell bodies for sacral nerves 2,3,4 located?

Answer 31

intermediate gray matter of the sacral spinal cord

Question 32

Where are the cranio parasympathetic postganglionic neurons located?

Answer 32

head or within walls of the thoracic and abdominal viscera

Question 33

What do the sacral parasympathetic neurons leave the spinal nerves as?

Answer 33

pelvic splanchic nerves

Question 34

Where do the pelvic splanchic nerves go to?

Answer 34

some enter the pelvic autonomic plexuses and supply the organs of the pelvis. some ascend out of the pelvis via the hypogastric nerves to be distributed to the hindgut structures via the inferior mesenteric artery (innervates the descending colon sigmoid colon, and rectum

Question 35

Where do the preganglionic parasympathetic nerve fibers of the oculomotor nerve travel to?

Answer 35

they travel to the ciliary ganglion in the orbit of the eye

Question 36

Where do the postganglionic parasympathetic nerve fibers of the ciliary ganglion travel to?

Answer 36

synapse onto the ciliary and sphincter muscles of the eye

Question 37

What does parasympathetic action of the eye accomplish?

Answer 37

accomodation of the lens and constriction of the pupil

Question 38

What are the two ganglia associated with the facial nerve?

Answer 38

submandibular and pterygopalatine ganglion

Question 39

Where is the submandibular ganglion located? What does the submandibular ganglion innervate?

Answer 39

Located at the base of the tounge, innervates the salivary glands located in the submandibular and subliguinal regions

Question 40

Where is the pterygopalatine ganglion located? What does it innervate? What is its action?

Answer 40

located behind the maxilla, postganglionic fibers innervate the lacrimal glands and the glands in the nasal cavity, pharynx and palate (action is to stimulate secretions)

Question 41

What ganglion is associated with the glossopharyngeal nerve? Where is it located?

Answer 41

otic ganglion located at the base of the skull near the foramen ovale

Question 42

What do the postganglionic nerve fibers of the otic ganglion synapse on? what is the function of this ganglion?

Answer 42

innervate the parotid gland to stimulate salivation

Question 43

Where are the ganglia of the vagus nerve located?

Answer 43

small ganglia located in pluxuses or in walls of thoracic or abdominal region

Question 44

What are some of the plexuses associated with the vagal ganglia?

Answer 44

cardiac, pulmonary, esophageal, celiac, superior mesenteric

Question 45

what are some actions of the parasympathetic system?

Answer 45

slows heart, constricts the arterioles of the heart, stimulates the digestive glands, relaxes the sphincter muscle of the gut, constricts the pupil and accomodates the lens for close vision