CN 1&2

Question 1

cn 1 and 2 are extensions?

Answer 1

of the forebrain

Question 2

T or F…. cn 1 and 2 do not have nuclei?

Answer 2

true

Question 3

alar plates become? formed from?

Answer 3

ectoderm > roof > alar plate > posterior horn > sensory/afferent

Question 4

basal plate becomes? formed from?

Answer 4

notochord > floor plate > basal plate > anterior horn > motor/efferent

Question 5

motor or sensory is medial or lateral?

Answer 5

mEdial = Efferent/motor (basal)
lAteral = Afferent/sensory (Alar)

Question 6

zone of autonomic neurons becomes the?

Answer 6

lateral horn

Question 7

what ventricle causes separation of posterior paltes?

Answer 7

4th ventricle

Question 8

why is repiratory epithelium unique when compared to olfactory?

Answer 8

respiratory cilia MOVES to ceates waves to allow mucus to move and olfactory does not

Question 9

what are the 4 cell types of olfactory epithelium?

Answer 9

1) olfactory cells
2) bowman’s glands
3) support cells
4) basal cells

Question 10

1) olfactory cells does what?
2) bowman’s glands
3) support cells
4) basal cells

Answer 10

1) 1st order nueron, located IN olfactory epithelium
2) secertory glands, push material to surface and prodcuce mucus to capture odors to start impulse at 1st nueron
3) keep ionic gradients the same so you do not fire a signal when you don’t want to
4) some regeneration

Question 11

what makes olfactory cells unique?

Answer 11

they can regenerate

Question 12

do you see olfactory nerves in disections?

Answer 12

no. cribiform plate on ethmoid bone has olfactory neurons passing through it, so in disections they are lost
* *we see 2nd NEURONS in the olfactory bulbs

Question 13

only 10% of what you smell is what you breath, so how do you smell?

Answer 13

1) RETRONASALLY from back of mouth
2) up to nasopharynx
3) thru coana
4) to nasal cavity
5) excite 1st order olfactory nerves emedded in epithelium
- –peripheral extensions out to cilia and central extensions up thru cribiform plate to synapse on
6) 2nd order neuron called MITRAL CELLS in olfactory bulb
7) 2nd travels thre MEDIAL and LATERAL STRIA to synpase directly on primary olfactory cortex
* *does NOT pass thru thalamus unless going thru limbic system for higher order stuff

Question 14

when does olfactory info pass thru thalames?

Answer 14

ONLY when participating in limbic system for higher order info like memory or emotion

Question 15

what are the 2nd order neurons of olfaction called?

Answer 15

mitral cells

Question 16

what cell is the 1st order neuron for olfaction?

Answer 16

olfactory cells

Question 17

explain the steps for taste

Answer 17

1) comes in thru glossopharengeal, vegus, and facial n
2) goes ipsilaterally to the solitary nucleus, which is important for any knid of visceral scent (wet sense= olf. and taste)
3) direct connections to reflexes, like gag
- -also the solitary tract which connects to upper tract (aka central tegmental tract) which will go up to the thalamus and insula

Question 18

the terminal part for taste and olfaction is the SAME. where?

Answer 18

INSULA

**tracts on how they get there is different

Question 19

solitary nucleus (olfaction and taste)

Answer 19

visceral reflexes

–direct synapses with efferent nuclei

Question 20

solitary tract (olfaction and taste)

Answer 20

input from visceral afferent

– merge to form central tegemental tract which will reach the limbic nuclei and insula

Question 21

what are the retinal cell layers?

where are they found??

Answer 21

1) photoreceptors
2) bipolar cells
3) ganglion cells
* *the first 3 neurons of optic pathway are ALL within the retina!

Question 22

vitreous cvity

Answer 22

clear gel the fills the space between the lens and the retina of the eyeball

Question 23

blind spot

Answer 23

where all the axons of 3rd order optic cells merge on retina

Question 24

what layers of dura does CN2 have aroudn it?

Answer 24

all 3 layers! (pia, aracnoid and dure)

**bc it is an extension of the CNS

Question 25

retina is divided into ___ and ____ havles

Answer 25

nasal and temporal

Question 26

what vessel supplies ALL of the retina?

Answer 26

central artery of retina

*if damaged you are blind

Question 27

axons from the ____ half of each retina decussate at the _____

Answer 27

nasal half

decussate at optic chiasm

Question 28

joined fibers at the optic chiasm continue as _______, most terminating on ___ order neruons in the lateral geniculate bodies

Answer 28

optic tracts

**4th order

Question 29

What and where is LGN?

Answer 29

in the thalamus and is cell bodies of the 4th order neurons of optic pathway

Question 30

visual fields =

Answer 30

hemifields

Question 31

axons from the 4th order neurons in the LGN fan out as optic radiations, terminating in the?

Answer 31

primary visual cortex of the occipital lobe (90%)

Question 32

10% of optic fibers do NOT terminate at the?

Answer 32

LGN

Question 33

if optic fibers do not terminate at the LGN, then what happens to them

Answer 33

they go back to the coliculi to synapse on efferents

**this is how we get reflexes (not really knowing or seeing before we respond)

Question 34

what sulcus separates the lower and upper halves of the primary visual cortex? name them

Answer 34

calcarine sulcus

• cuneus on top
• lingual on bottom

Question 35

L visual hemifiled is going to end up on the?

Answer 35

R visual tract
R geniculate nucleus
R optic radiations
R visual cortex

Question 36

the top visual feild (aka what you see) will be interpreted by the?

Answer 36

lingual gyrus on the bottom

Question 37

what is meyers loop?

Answer 37

inferior most radiations diving deep into terminal lobe to lingual gyrus

Question 38

what is the uncus? location of what cortex?

Answer 38

cleft in the temporal lobe where primary olfactory cortex is located

Question 39

most seizures occur in what lobe?

Answer 39

temporal

Question 40

halo test

Answer 40

drop of blood on papaer and if a shadow around outside occurs then there has been damage to cribiform plate
* tests for CSF rhinorrhea

Question 41

sella turcica houses?

what happens if there is a tumor of this?

Answer 41

pituitary gland

• first symptom is loss of vision
• causes compression of optic chiasm
• bitemporal hemianopia