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Flashcards in Test 2 Week 2 Deck (70):
1

There are three layers of the eye, called tunics

The outermost tunic contains the ____, which is transparent and the ____, which is the white of your eye and makes up most of the tunic...The transition zone between the cornea and sclera is called the ____

The middle tunic, also called the ____, contains the ____, which is the vascular layer of the eye and lines the sclera. This layer thickens as it becomes more anterior into the ___, with ciliary processes extending inward. The vascular layer continues as the ___, which is the colored part of the eye.

The inner tunic is also called the ____, and these layers are discussed in depth in further notecards






Cornea and the sclera, limbus

Uvea, Choroid, ciliary body, iris

Retina

2

Name the layers of the cornea starting from the anterior surface to the aqueous humor

Also, bowmans layer is attached to the corneal epithelium via ___

Also note cornea transplants (penetrating keratoplasty) is common

Corneal epithelium, Bownman's layer, Stroma, Descemet's membrane, and then corneal endothelium

^*CBSDC

Hemidesmosome

3

The middle tunic contains the vascular layer, and remember, this layer is pigmented

The ___ has dilator and constrictor smooth muscles to open and close to allow varied amounts of light through the pupil... The ___ surface has no epithelial lining and the ___ surface has dual layers of pigmented epithelial cells

The ____'s main job is focusing and they are attached to the lens via ___ and it regulates the tension of the zonule or suspensory ligament to have a role in accommodation

The ciliary processes main job is to secrete ___

Iris, anterior, posterior

Ciliary body, zonular fibers

Aqueous humor

4

The anterior and posterior chambers contain ___ humor (fluid like) and the vitreous cavity contains ___ humor (gel like substance)

Aqueous, Vitreous

5

The iris comes into contact with the lens and the capsule of the lens

As we said, the iris has dilator and constrictor smooth muscles and the muscle closest to the pupil are called the ____ muscle, which contraction causes a reduction in the diameter of the pupil aka miosis

The muscle further away from the pupil is the ___ and contraction causes the pupil to dilate aka mydriasis

Sphincter pupillae, dilator pupillae

6

The inner tunic aka the retina has an outer pigmented layer and inner retinal layer

The ___ 2/3rds is light sensitive (so we see with it) and the ___ 1/3rd is light-nonsensitive

The ___ is the "blind spot" where there are no photoreceptor cells because all the axons from all the ganglion cells meet here to be dumped into the optic nerve at the optic ___

The ___ is where the most photoreceptor cells are densely packed and mainly ___ are present here

Posterior, anterior

Papilla, optic disk

Fovea, cones

7

There are three general layers of the retina

The ____ cell layer's axons are what make up the optic nerve

The bipolar layer and the photoreceptor cell layers

Ganglion

8

However, there are 10 specific layers of the retina including the...

1) Layer in contact with the viteous body
2) Layer eventually has axons all come together to make optic nerve
3) Layer that has cells who's axons end up as optic nerve
4) Bipolar cell axons synapse onto ganglion cell dendrites
5) Layer with bipolar cell body cell layer
6) Photoreceptor cell axons synapse onto bipolar cell's dendrites
7) Contains cell bodies and nuclei of photoreceptor cells
8) Outer limiting membrane layer
9) Layer where actual seeing occurs
10) A epithelial layer

^** once we get past #10, we are into the middle tunic (choroid)

1) Inner limiting membrane
2) Nerve fiber layer
3) Ganglion cell layer
4) Inner plexiform layer
5) Inner nuclear layer
6) Outer plexiform layer
7) Outer nuclear layer
8) Outer limiting membrane
9) Inner and outer segments of rods and cones
10) Pigmented epithelium

9

At the ___, tightly packed cones are arranged at an angle to the pigmented layer and this allows the outer layers to not obstruct light as it comes through

The ___ is a yellow spot with the fovea centalis in the middle

Fovea centralis

Macula lutea

10

The layers of the ___ can separate due to trauma, vascular disease, or metabolic disorders/aging

Retina

11

The aqueous fluid, produced by the epithelial lining of the ciliary process, flows from the ___ chamber through the pupil into the ___ chamber to the trabecular meshwork and then into the canal of ___ to ____ veins and then ____ veins

***If you plug up the trabecular meshwork, the pressure inside the eyeball builds up (increased intraoccular pressure) and squishes the retina and this can cause ___
^** Most common is blockage of the canal of schlemm or inflammation preventing aqueous humor from reaching the trabecular meshwork

Posterior, anterior, schlemm, aqueous, episcleral

Glaucoma

12

The ciliary body has zonular fibers that attach to ___ fibers located at the ___ region of the lens

Coritcal lens, equatorial

13

Opacity of the lens caused by changes in the solubility of lens proteins, which impairs vision, often the result of aging and diabetes is called ___

Cataracts

14

The ____ lines the anterior surface of the eyeball up to the limbus (aka covers part of the sclera) and the inner surface of the eyelid and it's job is to keep the eyeball moistened

The __ glands exist inside the eyelid to allow the eyelid to float on the eye bulb itself

___ glands are located in the base of the eyelash (which are basically sebaceous glands)

Conjunctiva

Tarsal

Molls

15

Pink eye is when the ____ becomes infected aka this is called conjunctivitis

Conjunctiva

16

The membranous labyrinth contains the ___ and ___, along with the three ____ that open into the ___

The sensory receptors of the membranous labyrinth in the semicircular canals is the ____, the ____ utriculi and sacculi in the utricle and saccule, and the ___ in the cochlea

Utricle and saccule, semicircular ducts, utricle

Cristae ampullares, macula, organ of corti

17

The ___ duct extends from the vestibular area (saccule and utricle) to the ___ space around the brain

The endolymph communicates via the endolymphatic duct and ends in a dilated sac called the endolymphatic sac located in the ___ space of the brain

Perilymphatic, subarachnoid

Subdural

18

In the saccule and utricle, there are sensory receptor areas that are concerned with the detection of directional movement of the head called ___

Inside these maculae (mounds of tissue) are ___ which shift in position when the head changes position and sit ontop of the otolithic membrane.

There are cilia (stereocilia and the main kinocilium) that arise from ___ cells, which attach to the base of the maculae (aka the otolithic membrane) and these cells are also embedded in supporting cells to hold these hair cells in place

Maculae

Otolinths

Hair cells (type 1 and 2)

19

When the stereocilia move ___ the kinocilium, it causes the kinocilium to plunge inwards into the apical domain and caused ____ or those hair cells

When the sterocilia move ___ from the kinocilium, it causes the kinocilium to be lifted up and therefore ____ occurs

Side note, the stereocilia are linked via a protein filament called the ___

Towards, depolarization

Away, Hyperpolazation

Tip link

20

Inside the ___ of the semicircular canal are where the sensory cells are located

The structure that sits over the hair cells in the ampulla is the ___ and type ___ hair cells are most predominate at the ridge of the crista, and type ___ hair cells are most at the base

^*Movement of the head displaces the endolymph and the cupula to move the hair cells

Ampulla

Cupula, 1, 2

21

The stapes moves in and out of the ___ window and it is at the ___ window that the sound is interpreted

Oval, round

22

The chochlear duct has three components to it (aka spaces) called the ___, ___, and ___

^VMT

There are also membranes that separate these from each other including the ___ between vestibuli and media, ___ between media and tympani

Scala vestibuli, Scala media, and Scala tympani

Reissner's membrane, Organ of corti

23

******In the cochlea, inside the organ or corti, is a ___ membrane which is attached to the ___ hair cells *************

Tectorial, outer

24

Tympanic memrbane -> Malleus -> Incus -> Stapes -> Oval windown -> Scala vestibuli -> Up to the helicotrema -> Scala tympani ->Round window

Maybe???

25

********** Inside the scala media there is ___lymph and inside the sacal vestibuli there is ___ lymph and inside the scala tympani there is ___ lymph *************

Endolymph, perilymph, perilymph

26

So the ___ a light source is to the eye, the less the light rays must be refracted to focus them on the retina (they are already parallel)

The ___ a light source to the eye, the more they must be refracted (bent) so that the diverging rays can focus on the retina

Further

Closer

27

The ___ is the first site in the eye where refraction occurs (BENDING) and it does about ____ of the light bending

The next bending of the light, which adds a variable degree of refraction is via the ___

^** The variable component is due to the muscles changing their shape

Cornea, 2/3rd

Lens

28

Accommodation requires three things including ___, ____, and ____

When trying to see something near, you want the lens to be _____ (since you need to bend the light rays more, than if they are coming in parallel from a far away distance, which you would then want the lens to be ____)

Ciliary muscles, suspensory ligament, and the lens itself

Rounder, flatter

29

****** To see something clear up close, we want the lens to be round (aka globular) so that it can have an increased refractive power, and this is done by the ciliary muscles ___ and the suspensory ligaments ___

For far vision, we want the lens flat, so the ciliary muscles ____ and the suspensory ligaments ___ their tension

*******

Contracting, relaxing

Relax, increase

30

For near vision, there something called the near response and this consists of three things including ___ of the ciliary muscles (like we already talked about, which causes thickening of the lens), ____ of the eyes to the point of focus, and ___ of the pupil (to reduce the amount of light to enter and this eliminates some of the diverging light rays to allow us to focus better)

Contraction, convergence, constriction

31

High levels of glutamate occur in the ___, and in the ___, there is decreased levels of glutamate

Dark, light

32

For the vertical pathway for cones, a photoreceptor is struck by a photon of light and this causes the cone to become ___polarized. Next, the NT glutamate levels being released to the bipolar cell are ____ and this rids the bipolar cells of their previous inhibition

Now there are two types of bipolar cells, ___-center bipolar cells must be activated by a photoreceptor in the CENTER of their receptive field, causing ____ of the bipolar cell (if photoreceptor activates surrounding region, it becomes hyperpolarized)

The other type is ___-center bipolar cells, which must be activated by a photoreceptor in the surrounding region to cause _____, and in the center causes ____

Hyperpolarized, Decreased

On, depolarization

Off, depolarization, hyperpolarization

33

In the dark, the photoreceptor activates an ON center bipolar cell because the photoreceptor constantly releases glutamate, which binds to the ___ receptors on the ON-cell. This causes the ON-center bipolar cell to be ____ due to a ____ in cation influx, and therefore inactive

If the photoreceptor is stimulated by light, it decreases its glutamate release, no longer binds to the metabotropic receptors on the ON center bipolar cell, and this allows the bipolar cell to become ____ due to an ___ cation current into the cell

Bipolar cells and photoreceptor cells DO NOT generate action potentials

**So in other words, glutamate hyperpolarizes ON-center bipolar cells

Metabotropic, hyperpolarized, decrease

Depolarize, increased

34

In the dark, the photoreceptor activates an OFF center bipolar cell because the photoreceptor constantly releases glutamate, which binds to the ___ receptors on the OFF-cell. This causes the OFF-center bipolar cell to be ____ due to a ____ in cation influx, and therefore activated

If the photoreceptor is stimulated by light, it decreases its glutamate release, no longer binds to the AMPA receptors on the OFF center bipolar cell, and this allows the bipolar cell to become ____ due to a ___ cation current into the cell

Bipolar cells and photoreceptor cells DO NOT generate action potentials

** So in other words, Glutamate depolarizes OFF-center bipolar cells

AMPA, depolarized, increased

Hyperpolarized, decreased

35

Ganglion cells are also ON and OFF center cells and the bipolar cells (depends what the bipolar cell is)

The bipolar cells release ___ to excite the ganglion cells

ONLY THE GANGLION CELLS MAKE ACTION POTENTIALS

Glutamate

36

The vertical pathway for RODS are composed of many rods, and converge ALWAYS on one ___-center bipolar cells (expressing metabotropic receptors)

However, these On-center bipolar cells don't connect to a ganglion cell, instead they attach to an ____ cell, when then synapse on a ___ cell and THEN activate a ganglion cell

RODS due vision in ___ light

*******So when the see A-11, think RODS and vision in the dark***

On

A-11 Amacrine, Cone On-center Bipolar cell

Low

37

___-center cells tell us where something is, and ___-center cells tells us where it ends

^** So these cells start to allows us to determine edges

Also, the amacrine and horizontal cells add to that by providing ____ signals that modify the activity of the nearby photoreceptors

On, OFF

Inhibitory

38

The left temporal retina is activated by light coming from the ___ visual field

The left nasal retina is activated by light coming from the ___ visual field

The right temporal retina is activated by light coming from the ___ visual field

The right nasal retina is activated by light coming from the ___ visual field

At the optic chiasma, the axons from the ___ retina on each side cross and join their axons from the temporal retina so that all info from the right visual field is sent to the same part as the brain and same for left visual field

In the case of the right visual field, it goes to the __ side of the brain and for the left visual field, it goes to the __ side of the brain

Right

Left

Left

Right

Nasal

Left, right

39

One of the first synapses we can have for reconstructing the visual image, is at the ___

This structure has 4 different functions including controlling the motions of the eye, controlling focus, identifying major elements within our visual image, and identifying motion

Lateral geniculate body

40

In the primary visual cortex (V1), the axons that left the LGN synapse in layer ___ of the cortex

The cortex is composed of ___ that start from the surface of the cortex and extend through all 6 layers, they are important in distinguishing ___

*^^^ So really, the major function is to take the info from the LGN and identify the edges/contours

4

Columns, edges

41

The ____ is where the photoreceptors are densest and have the highest acuity and therefore a large portion of the primary visual cortex is taken up by this (most cortex dedicated to the macula)

In the macula, it is mainly ___

In the periphery, it is mainly ____

Macula

Cones

Rods

42

The major job of V2 is to identify disparities in the visual image presented by the two eyes in order to detect ___ perception

Depth

43

For color vision, the part of the cortex responsible is V__ and within the columns there are collections of neurons called ____ that enable color detection

V1, blobs

44

The major job of V___ is complete processing of the color inputs

(So V1 started it, and V4 finishes it for color)

V4

45

Once we process in the primary visual cortex, we just know what the image looks like but we can't name it, draw it, etc...

This is only accomplished via higher processing of the visual inputs and this occurs via a ___ pathway that leaves the occipital cortex and relays information to the ___ corticies so that we can perform motor actions based on visual input

The ____ pathway relays information to areas of the brain involved in higher processing of sensory input to allow us to name things or copy the object (aka what did I see?)

Dorsal, motor

^* THINK DANCE MARATHON

Ventral

46

Perilymph (in the scala vestibuli and scala tympani) is high in ___ and low in ___
^Similar to ECF

*****The endolymph (in the scala media) is high in ___ and low in ___
^Similar to intracellular fluid

Na, K

K, Na (LAN - Low is Na)

47

In the inner ear, the impact of the stapes on the ___ causes the ___ membrane to vibrate at the same frequency of the sound

____ frequency causes maximum vibration of the basilar membrane closest to the oval windown

___ frequency causes maximum vibrations of the basilar membrane farthest away from the oval window

Oval windown, basilar

High (short wavelength)

Low (long wavelength)

48

The tectorial membrane ____ (does or does not) move

It has hair cells attached to it, so when the basilar membrane vibrates, the tectorial membrane does not move and this causes the hair cells to bend in one direction or another

It is the ___ hair cells that are important for hearing

Does not

Outer

49

Remember, bending the hair cells (stereocilia) towards the kinocilium, ____ the cell via opening _____ channels

^** Even though most of the time K moves out of the cells due to its concentration gradient, here, K is higher outside than inside so therefore it moves into the cell

*Ca2+ is also involved, but K+ is the major reason for depolarization and APs

Depolarize, K (potassium)

50

For the hearing pathway, via the vestibulocochlear nerve (CN 8), the path splits into two parallel pathways in the ____

The ___ path starts to process temporal and spectral features of sound (aka timing and pitch aka nature of sound like a high or low sound)

The ___ path integrates acoustic info with somatosensory info for localizing sound (aka where the sound started from)

cochlear nucleus

Ventral

Dorsal

51

The ____ generates a map of the intraaural TIME differences (aka how the sound arrived at the two ears differently)

The ____ generates a map of the intraaural INTENSITY differences (aka how the sound arrived at the two ears differently)

Medial superior olive

Lateral superior olive

52

The ____ suppresses information related to echoes and arrives at a final estimation of the sound location on the horizon (because echoes interfere with location)

The ____ takes the location data from the IC and adds a third dimention to it (aka vertical height) to create the spatial map of the sounds location

Inferior colliculus

Superior colliculus

53

The primary auditory cortex (A1) has a tonotopic representation of the sounds (aka oriented by tone) so it can determine low frequency sounds that activate more ___ areas or high frequency sounds that activate more ___ areas

It allows for the beginning of knowing what the sound is

Rostral, caudal

54

The vestibular apparatus (consists of the utricle, saccule, and semicircular canals) is designed to detect ___ (linear or angular/rotational)

The semicircular canals (anterior, horizontal, and posterior) detect ___ acceleration and the saccule and utricle detect ___ acceleration

Acceleration

Angular, linear

55

More specific, the utricle detects ___ motion

The saccule detects ___ motion

The turning motion is best detected by the ___ canals

Falling backwards activates the ____ canal

Falling forwards activates the ___ canal

Horizontal linear

Vertical linear

Horizontal (also called lateral sometimes)

Posterior

Anterior

56

In the vestibular apparatus, inside the semicircular canals, there is an ____ which has hair cells and their cilia projections into the cupula and it is this structure that plays a role in activating the vestibular organs

In the vestibular apparatus, inside the utricle and saccule, there is an ____ which has sterocilia, kinocilium, etc...

And motion of the body moves the ___ to move the ampulla or macula

Ampulla

Macula

Endolymph

57

*********If the anterior semicircular canal is active (aka I am falling forward) the ___ muscle is activated and the ___ muscle is inhibited
^ (eyes move up)

*********If the posterior semicircular canal is active (aka I am falling backward) the ___ muscle is activated and the ___ muscle is inhibited
^ (eyes move down)

*********If the horizontal semicircular canal is active (aka spinning) for the eye ipsilateral to the rotation, the ___ muscle is activated and the ___ muscle is inhibited. For the eye contralateral to the rotation, the ___ muscle is activated and the ___ muscle is inhibited
^ (So if you rotate right, your right eye is the ipsilateral eye, etc)

Superior rectus, Inferior rectus

Superior oblique, inferior oblique

Medial rectus, lateral rectus, lateral rectus, medial rectus

58

Cortical and cerebellar involvement in the vestibulooptic reflexes ____ the reflex to allow for voluntary motion

Suppress

59

The anterior chamber is in front of the ___ and the posterior chamber is behind it

The ___ cavity is what gives our eyes its shape (don't confuse this with the posterior chamber)

Iris

Vitreous

59

Neurons that change their firing rate in response to changes in local temperature are called ____

They can be warm or cold sensitive and if they are warm, they express ____ V1-V4 (V stands for vanilloid, which is also activated via ___)

Cold receptors are also TRP and are activated also by ___

Note that normal body temp is 36.7 C or 98.06 F

Thermoreceptors

TRP, capsaicin (found in hot peppers)

Menthol

60

The____ is the controller for the thermoregulatory system and also has connections to control hormonal, autonomic, and behavioral changes that are part of thermoregulation

Response to heat is the ___ portion of the hypothalamus
^ Activates heat ___ behaviors

Response to cooling is in the ___ portion of the hypothalamus
^ Activates heat ____ behaviors

Hypothalamus

Anterior, loss

Posterior, production

61

The ____ has a set point (the desired value) for core temperature, which is determined by neural activity

hypothalamus

62

Thermoreceptors are located in the brain (the core), gut, viscera, and skin

The ones in the ___ tell you about your environmental threats

The ones in the ___ sense core temperature and since food ingested can change body temperature, they must have thrermoreceptors

The ones in the brain are in the ____ and ___ regions of the hypothalamus, which relay their info to other areas of the hypothalamus and also there are 3x more ___ sensitive receptors than cold

*******So the Preoptic and Superoptic regions of the hypothalamus, and the Viscera tell us about ____ temperature and the cutaneous about the ___ temperature ********

Skin

Gut/viscera

Preoptic and superoptic, warm

Core, external

63

The hypothalamus takes all the afferent info and determines a set point, compares it to the core temperature, and decides if it needs to respond to changes

If there does need to be a response, and the body produce heat, it can do some via the sympathetic nervous system (ANS) or hormones and this can cause

^** This is all done in the posterior portion of the hypothalamus

1) Muscular activity (shivering), which increases motorneuron excitation
^** Shivering is produced in the ____ part of the hypothalamus

2) non-shivering thermogenesis (non-muscular), which has a strong ____ influence including thyroxin, epinephrine, etc.... And also an increase in ___ intake and finally, ___ tissue

Dorsomedial posterior hypothalamus

Hormonal, food, brown adipose

64

____ allows the use of ATP without directing the energy (in other words, you can hydrolyze ATP and then nothing happens to the energy, which makes it become heat)

It is driven by the ___ nervous system and circulating ____

^** It is found a lot in infants, but it also exists in humans

Brown adipose tissue

Sympathetics, epinephrine

65

If the body needs to loose heat, it is done in the anterior portion of the hypothalamus and can occur via losing heat as water evaporates

Can occur as insensible (respiratory) or sweating (controlled)

____ is the movement of molecules away from contact (air heating and rising)

____ is the transfer of heat between objects in physical contact with one another

____ is the transfer of heat between 2 objects that are not in physical contact

Convection

Conduction

Radiation

66

For example, lets say TB (Core body temp) > TS (Set point temp).... We would want to lower the TB so that it can get back to the TS and therefore we want to increase heat loss and decrease heat production

In order to increase heat loss, we would ___ the amount of blood being sent to the skin, sweat (evaporative heat loss), and possibly pant (insensible heat loss)

We would also want to decrease heat production via not eating, etc...

Increase

67

The innervation to sweat glands in via the _____ nervous system, and ____nergic via ACh as the NT binding to a _____ receptor

To make sweat, plasma from blood vessels and ions (Na and Cl) gets moved to sweat glands.

When it's not super hot out, the fluid moves up the duct of the sweat gland, ___ and ____ get reabsorbed (back into the blood), but at low flow rates, more ___ gets reabsorbed and you end up with ____ water and ___ Na+ in your sweat (which is why it's salty)

If it's really hot out, and your flow rate is high, you don't have enough time to reabsorb the water so you end up with ____ water and ___ sodium content

Sympathetic, cholinergic, muscarinic

Water and Na, water, lower, higher

Higher, lower

68

With a fever, the hypothalamus causes the ___ to increase, which is driven via Prostaglandins like E2, and this causes the body temp to also increase to meet the set point

In other words, since now your Tb is less than your Ts, you increase heat production and decrease heat loss when you first come down with an infection and a fever is produced

Once you kill off the infection, the Ts goes back down to normal and now the Tb is left higher, so you end up with decreasing heat production and increased heat loss (sweating)

Set point

69

In hypo and hyperthermia, the set point is ____ but there are uncontrolled changes in body temperature

Normal