Cranial Nerves 1-3

Question 1

are cranial nerves part of the PNS or CNS?

Answer 1

peripheral nervous system

EXCEPT CN 1 and CN 2

Question 2

are cranial nerves target structures ipsilateral or contralateral?

Answer 2

mainly ipsilateral, some have contralateral targets

Question 3

motor branches of cranial nerves

Answer 3

multipolar

Question 4

somatosensory branches of cranial nerves

Answer 4

psuedounipolar

Question 5

special sensory

Answer 5

bipolar

Question 6

peripheral nerve layers

Answer 6

epineurium, perineurium, endoneurium

Question 7

epineurium

Answer 7

outermost layer that binds fascicles together

contains blood vessels

Question 8

perineurium

Answer 8

bind groupings of axons into fascicles

Question 9

endoneurium

Answer 9

delicate layer of CT surrounding nerve fiber

Question 10

cranial nerve nuclei

Answer 10

somatic, branchial, autonomic and visceral motor

somatosensory, special, autonomic and visceral sensory

Question 11

first order neuron

Answer 11

presynaptic

periphery to spinal cord

Question 12

second order neuron

Answer 12

postsynaptic

spinal cord to thalamus

Question 13

third order neuron

Answer 13

thalamus to sensory cortex

Question 14

olfaction

Answer 14

chemical interactions btw air molecules and chemoreceptors within membranes of receptor cells in nasal cavity = smell

Question 15

olfactory epithelium

Answer 15

sensory organ in nose

Question 16

olfactory sensory receptor cells

Answer 16

hair cells - bipolar neurons

Question 17

supporting cells

Answer 17

glial cells

support, nourish, insulate, detoxify olfactory cells

Question 18

basal stem cells

Answer 18

help olfactory cells out

Question 19

olfactory glands

Answer 19

create the mucus

Question 20

what are the 3 main layers of the eye

Answer 20

fibrous outer layer
vascular middle layer
retinal inner layer

Question 21

fibrous outer layer

what is in this layer

Answer 21

irregular, avascular

sclera and cornea

Question 22

sclera

Answer 22

attaches eye w eyelid, dural sheath of CNII and tendons of extra-ocular muscles

Question 23

cornea

Answer 23

outermost lens of eye - controls and focuses incoming light

Question 24

vascular middle layer

what is in this layer

Answer 24

vascular

choroid, ciliary body, iris

Question 25

choroid

Answer 25

contains blood vessels btw retina and sclera

Question 26

ciliary body

Answer 26

contains ciliary processes which contain capillaries and attach to ligaments that help suspend lens and ciliary muscle (visual accommodation - CNIII)

Question 27

iris

Answer 27

contains smooth muscle fibers that act on pupil color

Question 28

how many layers is in the retinal inner layer and what are they

Answer 28

7 layers ``` pigment epithelium photoreceptor layer outer and inner nuclear layers outer and inner synaptic layers ganglion cell layer (host ganglia) ```

Question 29

what lies within the photoreceptor layer

Answer 29

rods: dim light vision, gray images, low acuity cones: bright light vision, color images, high acuity

Question 30

what specialized areas are in the retinal inner layer

Answer 30

optic disc: site where optic nerve and blood vessels enter/exit the eye macula lutea: visual axis, contains central fovea - clean and crisp vision

Question 31

lens

Answer 31

functions to bend light to focus image on retina

Question 32

vitreous humor

Answer 32

btw lens and retina holds retina in place contains phagocytes - remove floating debris

Question 33

anterior cavity

Answer 33

btw cornea and lens | contains aqueous humor - filter blood plasma that nourishes lens and cornea

Question 34

meninges

Answer 34

dura, arachnoid, pia mater develops in utero, comes from the optic vesicle which is an out pocket region of the forebrain, builds out of it - technically CNS

Question 35

pupillary response to light

Answer 35

reflex light entering pupil activates retinal ganglion cells --> optic nerve --> optic chiasm --> bilateral pretectal area --> EW nuclei --> project ipsilateral motor efferent via oculomotor nerve to ciliary ganglion neurons --> pupil constriction

Question 36

edinger-westphal nuclei projects where

Answer 36

ipsilaterally on both sides via oculomotor nerve to ciliary ganglia to the pupillary constrictor muscles

Question 37

when light is shine in one eye what should the response be

Answer 37

direct response in ipsilateral eye and a consensual response in contralateral eye

Question 38

accommodation response

Answer 38

not a reflex, checks on brain to control eyes occurs when visual objects moves from far to near, you get pupillary constriction, accommodation of lens ciliary muscle and convergence of eyes by extraocular muscles (EOMs)

Question 39

how does the accommodation response start

Answer 39

follows entire pathway of optic pathway all occurs bilaterally