quiz CN 1 And 2

Question 1

What is Cranial nerve 1?

Answer 1

Olfactory nerve

Question 2

What kind of neuron is the olfactory neurons? And what type (uni/bi)

Answer 2

It is a primary sensory neurons

Bipolar

Question 3

Where are the primary sensory neurons for the olfactory neurons lie?

Answer 3

Found in olfactory epithelium lining superior part of nasal cavity

Question 4

What covers the olfactory epithelium?

Answer 4

A thin layer of mucus

Question 5

Olfactory neurons are supported by what kind of cells

Answer 5

Supporting cells

Question 6

What do olfactory “hairs” function as?

Answer 6

Function as receptors.

Question 7

Central processes (axons) for olfactory nerves are conveyed where and how many are there

Answer 7

Axons are collected into 10 to 20 olfactory nerves that convey information to the olfactory bulbs

Question 8

Are olfactory neuron axons myelinated?

Answer 8

They are unmyelinated, but covered by Schwann cells

Question 9

Where do olfactory nerves pass to? (Pathway)

Answer 9

Pass through the cribiform plate, part of the ethmoid bone. They enter the olfactory bulb and synapse on dendrites of mitral cells. Synaptic glomeruli are formed at the synapses

Question 10

How many neurons is this pathway for olfactory?

Answer 10

2 neuron pathway

Question 11

What cells are the secondary sensory neurons in the olfactory pathway

Answer 11

Mitral cells

Question 12

Where are the mitral cells located?

Answer 12

In the olfactory bulb

Question 13

Mitral cells relay information from where?

Answer 13

Relay information posterior via the olfactory tract

Question 14

Where do the fibers split for the mitral cells?

Answer 14

At the anterior perforated substance, the tract fibers split into medial and lateral olfactory striae

Question 15

Where do Medial Stria fibers go?

Answer 15

Cross midline via anterior commissure and travel to opposite olfactory bulb

Question 16

Do we segregate smell?

Answer 16

No

Question 17

Where do the lateral stria fibers go?

Answer 17

Carry information to the primary olfactory cortex; periamygdaloid and prepiriform area, including the uncus (Brdmn 34) on the medial aspect of the temporal lobe

Question 18

Lateral stria fibers also go to the secondary olfactory cortex, what is included in this

Answer 18

Entorhinal area, located in parahippocampal gyrus (Brdmn 28)

Question 19

What Brodmann areas are included in the olfactory pathway

Answer 19

34, 35, 28

Question 20

What kind of traumas can make patients lose smell temporarily?

Answer 20

Head traumas

Question 21

What test can be done to perhaps test for dementia

Answer 21

Peanut butter test

Question 22

What is another name for loss of smell?

Answer 22

Anosmia

Question 23

Is it possible to not be born with CN 1?

Answer 23

Yes, but very rare

Question 24

If you have CSF leakage in the nose, how can you test if it truly is?

Answer 24

Halo sign test

Question 25

What is the terminal nerve (other pathway)

Answer 25

Info from receptors on nasal septum | Autonomic in function

Question 26

What is the vomeronsal nerve (other pathway)

Answer 26

Poorly developed in humans, believed to be important in tracking prey

Question 27

What is the name for cranial nerve 2

Answer 27

Optic nerve

Question 28

The eye is a sensory organ of vision. What three layers make it up?

Answer 28

Outermost layer - fibrous tunic Middle layer - vascular tunic Innermost layer - retina (it has ten layers)

Question 29

What does the fibrous tunic consist of

Answer 29

Sclera - white | Cornea - clear

Question 30

What does the vascular tunic consist of

Answer 30

Ciliary body Iris; color part, made up of two muscles Choroid

Question 31

The optic nerve is a how many neuron pathway

Answer 31

It is a 4 neuron pathway

Question 32

What are the ten layers of the retina? Outside to in

Answer 32

``` Pigmented layer Photosensitive outer segments External limiting layer Outer nuclear layer Outer plexiform layer Inner nuclear layer Inner plexiform layer Ganglion cell layer Nerve fiber layer Internal limiting membrane ```

Question 33

What is the pigmented layer adjacent to?

Answer 33

Choroid

Question 34

What doesn’t eh photosensitive outer segment contain?

Answer 34

Rods and cones

Question 35

Outer nuclear layer contains what

Answer 35

Rod and cone cell bodies

Question 36

Outer plexiform layer contains what

Answer 36

Rods and cones synapse with bipolar cells here

Question 37

Inner nuclear layer contains what

Answer 37

Cell bodies of bipolar cells

Question 38

Ganglion cell layer contains what

Answer 38

Ganglion cell bodies

Question 39

Nerve fiber layer contains what

Answer 39

Retinal ganglion cell axons. These fibers are NOT myelinated

Question 40

What is the internal limiting membrane

Answer 40

A glial boundary separating the retina from the vitreous body

Question 41

What part of the photoreceptors is either cylindrical(rod shaped)or cone shaped (tapered)

Answer 41

Distal end of the photoreceptor

Question 42

What are the three types of cones

Answer 42

Red, green blue

Question 43

Cones do what?

Answer 43

Receive color information and help with clarity of image

Question 44

Do cones require light?

Answer 44

Require adequate light to function best (the more the better)

Question 45

Where are cones mostly concentrated?

Answer 45

More concentrated toward center of retina(fovea)

Question 46

What do rods do?

Answer 46

Sense only light vs dark

Question 47

Are their rods in fovea?

Answer 47

No rods in fovea, periphery of retina is almost completely composed of rods

Question 48

Color blindness is what kind of condition

Answer 48

Multiple forms mostly sex linked

Question 49

When depolarized, what do photoreceptors do?

Answer 49

Relay information to bipolar cells by synapsing in the outer plexiform layer.

Question 50

Where are bipolar cell bodies found?

Answer 50

In the inner nuclear layer

Question 51

Where do the bipolar cells relay information to?

Answer 51

The ganglion cells, the synapse occurs in the inner plexiform layer

Question 52

Axons from ganglion cells are conveyed where?

Answer 52

Conveyed in the nerve fiber layer toward the optic disc. These axons are carried in the optic nerve after leaving the eyeball. The optic nerves enter the skull through the optic canal and untie to form the optic chiasma

Question 53

Are nerve fiber layer axons myelinated

Answer 53

No

Question 54

Are optic nerve axons myelinated

Answer 54

Yes

Question 55

What cells form myelin for the optic nerve axons

Answer 55

Infasicular oligodendrocytes

Question 56

How do the fibers run in the optic chiasma

Answer 56

Fibers from medial (nasal side) of each retina will cross, while fibers from lateral (peripheral side) of the retina will not cross. Fibers split to form the optic tracts

Question 57

Where does the optic tract travel around?

Answer 57

Travels around the cerebral peduncles and fibers synapse on one of three nuclei of termination

Question 58

What are the nuclei of termination and their characterisitics

Answer 58

Majority synapse in lateral geniculate body and are relayed to the cerebral cortex in the occipital lobe (17) Fibers synapsing in the superior colliculus where information is relayed to the tectospinal tract Some fibers synapse in the pretectal nucleus of the midbrain. These fibers deal with light reflexes

Question 59

What two muscles are influenced by the tectospinal tract

Answer 59

Sternocleidomastoid | Trapezius

Question 60

If you have a lesion in the optic nerve, what happens?

Answer 60

Blind in one eye

Question 61

If you have decussating fibers of the optic chiasma being cut or lesioned, what happens

Answer 61

Peripheral vision gone

Question 62

If you have a lesion in the optic tract, what happens

Answer 62

Half of vision field gone

Question 63

What visual reflexes does CN 2 deal with

Answer 63

Direct and consensual light reflexes Accommodation reflex Corneal reflex Convergence

Question 64

What does direct and consensual light reflex do?

Answer 64

One eye will constrict while other dilates

Question 65

What does accommodation reflex do?

Answer 65

Going from far sight to something close in view, lens becomes more convex to focus on near objects

Question 66

What does corneal reflex do

Answer 66

Soft cotton balls, lightly touch cornea, patient should pull away and blink

Question 67

What does convergence do

Answer 67

Pulling eyes together or inward