Chapter 13 Cranial Nerves

Question 1

List components of the PNS

Answer 1

Includes: sensory receptors, peripheral nerves and ganglia, and efferent motor endings

Question 2

outline the events that lead to sensation and perception in reference to sensory, motor, and integration

Answer 2

sensation - allows information from PNS to CNS
perception - is our interpretation found within the integration process of the CNS, allow us to initiate signals to our effectors down the efferent pathways

Question 3

general structure of a nerve

Answer 3

endoneurium: tissue surrounding individual axons and their myelin sheaths
perineurium: tissue surrounding a bundle of axons (fascicle)
epineurium: tissue surrounding bundle of fascicles

Question 4

what is the mnemonic for remembering the order of cranial nerves

Answer 4

Old opie occasionally tries trigonometry and feels very gloomy, vague, and hypoactive
Olfactory
optic
oculomotor
trochlear
trigeminal
abducent
facial
vestibulocochlear
glossopharyngeal
vagus
accessory
hypoglossal

Question 5

Indicate the body region and structures innervated by olfactory nerve (I)

Answer 5

found in cerebrum (olfactory bulb)
sensory nerve
functions for smell

Question 6

Indicate the body region and structures innervated by the Optic Nerve (II)

Answer 6

connects to cerebrum
sensory nerve
functions for sight

Question 7

Indicate the body region and structures innervated by Oculomotor nerve (III)

Answer 7

connects to midbrain
Motor nerve
functions 4-6 eye muscles

Question 8

what are the somatic and autonomic functions the Oculomotor nerve serves?

Answer 8

somatic: raises eyebrows
autonomic: pupillary reflex

Question 9

Indicate the body region and structures innervated by Trochlear Nerve (IV)

Answer 9

connect to midbrain
motor nerve
functions 5th eye muscle (moves eye downward)

Question 10

Indicate the body region and structures innervated by Trigeminal Nerve (V) and what do the three subsections serve?

Answer 10

connects to pons
both sensory and motor
- V1: Ophthalmic division: sensory to the skin around eyes/scalp/forehead
- V2: Maxillary division: sensory to within the nasal cavity mucosa/ palate/ upper teeth/ upper lip/ skin of cheek
- V3: Mandibular division: sensory to lower teeth/jaw
Motor to muscles of mastication (opening and closing jaw)

Question 11

Indicate the body region and structures innervated by Abducent Nerve (VI)

Answer 11

connects to pons
motor nerve
functions the 6th eye muscle (abducts the eye)

Question 12

Indicate the body region and structures innervated by Facial Nerve (VII)

Answer 12

connects to pons
both motor and sensory
sensory to taste (2/3 anterior tongue)
motor to facial muscles, lacrimal glands, and salivary glands

Question 13

Indicate the body region and structures innervated by Vestibulocochlear Nerve (VIII)

Answer 13

connects to medulla oblongata
sensory nerve
2 branch functions:
1) vestibular: balance/equilibrium
2) cochlear: hearing

Question 14

Indicate the body region and structures innervated by Glossopharyngeal Nerve (IX)

Answer 14

connects to medulla oblongata
sensory nerve
functions taste (1/3 posterior tongue), tonsils, and back of throat

Question 15

Indicate the body region and structures innervated by Vagus Nerve (X)

Answer 15

connects to medulla oblongata
both sensory and motor
sensory to larynx esophagus, and viscera
motor to laryngeal muscles, heart and other viscera

Question 16

Indicate the body region and structures innervated by Accessory Nerve (XI)

Answer 16

connects to medulla oblongata
motor nerve
2 branch functions
1) cranial branch: help control swallowing
2) spinal branch: controls trapezius and sternocleidomastoid muscles

Question 17

Indicate the body region and structures innervated by Hypoglossal Nerve (XII)

Answer 17

connects to medulla oblongata
motor nerve
functions for the muscles that move the tongue

Question 18

what is the smallest cranial nerve?

Answer 18

trochlear nerve

Question 19

what are the nerves that are associated with muscles of the eyes?

Answer 19

Oculomotor nerve (III)
Trochlear nerve (IV)
Abducent nerve (VI)

Question 20

what is the mnemonic for remembering the sensory/motor functions of the cranial nerves?

Answer 20

Some says money matters, but my brother says sizable brain matters most

Question 21

describe the general structure of a spinal nerve and general distribution of its rami

Answer 21

ventral roots contain motor fibers
dorsal roots contain sensory fibers
ventral and dorsal roots divide into large ventral ramus and small dorsal ramus

Question 22

what is a nerve plexus and why is it important

Answer 22

interlacing nerve networks of various rami that occur in separate regions along the spinal cord
advantage of this is that damage to one spinal segment or root cannot completely paralyze any limb