Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Med Neur 2 > Visual 2 > Flashcards

Visual 2 Flashcards

1
Q

These are mores sensitive to light and have slow integration time

A

rods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

These have poor spatial resolution

A

rods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

These have more pigment and are less directionally sensitive

A

rods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

These are less sensitive to light and have fast integration time

A

cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

These give us high spatial resolution

A

cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

These hae less pigments and are directionally sensitive

A

cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Per eye you have______ rods

and ____cones

A

100 million

5 million

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Key dif btwn rods and cones are rods

A

saturate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

At low levels of light, rod …

A

reaches its max response, at room level, rods are saturated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Most of the time,vision is based on

A

cones or 5% of photoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Photorecetpors _____ in response to light

A

hyperpolarize

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Photopigment =

A

chomophore + opsin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Chromophore conformation is

A

11-cis retinal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

photopig is embedded in

A

OS layer (80% OS is photopigment)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

11-cis-retinal absobs light at

A

375 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Opsin will “_____” absorption spectrum

A

red shift

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Changes in chromophore will….

A

initiate transduciton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what kind of protein receptor is photopigmetn

A

GPCR with chormophore burried in middle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

rods absorb strongest in

A

blue-green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

photopigments are characterized by:

A

efficiency with which they absorb light of diff wavelengths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

photoreceptors cant register the wavelenth of photons the catch “the output depends on quantum catch, but not upon WHICH quanta are caught”

A

concenpt of univariance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Photoreceptors are _______

A

colorblind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do we tell what dif types of colors we see

A

photoreceptors give input to ganglion cell based on quantam catch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Once we absorb light, begin phototransduction which begins with:

A

Isomerization: shift from 11-cis to all trans conformation as we slam against the transmembrane domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Isomerization from 11-cis chromophore to all trans will cause:

A

activaiton of opsin protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Once Opsin is activated, it will activate

A

transducin (g protein)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Once transducine is activated it will

A

activate PDE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

PDE will do what to cGMP

A

turn it to GMP which closes ion channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

low cGMP closes ion channels resulting in

A

hyperpolarization (inward flux of Ca++ and Na+ blocked)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

path of phototransduction

A

isomerization–>opsin–>transducin–>PDE–> takes cGMP to GMP–> results in hyperpolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Where is atRAL reduced to all trans retionol (atROL)

A

outter segment via NADPH all trans retinal specific dehydrogenase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

this guy is a slave to photoreceptor regeneration

A

RPE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

this guy transferes at ROL across the IPM

A

IRBP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

which degernates first, cones or rods

A

rods, bc cones have alternate source of 11cRAL other then RPE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

viagra has this and can interfere with basic phototransduction and lead to changes in rod and cone OS function

A

PDE5 inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

light falling w/in receptive field of a neuron influences the activity of that neuron
every neuron that is higher order than the photoreceptor has a ‘field’ of photoreceptors that give it input

A

concentp of receptive field

37
Q

All photoreceptors will ______ in reponse to light

A

hyperpolarize

38
Q

when photoreceptors hyperpolarize they…

A

release less NT

39
Q

Photoreceptrs are _____ cells because light hitting them turns them_____

A

OFF

OFF

40
Q

when there is no light on a photreceptor it will

A

depolarize and release glutamate

41
Q

Photoreceptors hyper and depolarize in a ______ fashion and relase NT’s in the same manner

A

graded

42
Q

Photoreceptors do or do not produce action potentials

A

DO NOT!!!!

43
Q

When a cone is depolarized it will release

A

glutamate (ig it’s excitatory, but not always)

44
Q

Cones respond to light the same way, but single cone gives rise to

A

2 parallel pathways via connecting 2 dif bipolar cell types

45
Q

The bipolar cell that is “ON” center
Light in it’s receptive field results in _____
and they have ______ synase with cone

A

cell depolarizing

sign reversing

46
Q

On center bipolar cells have ______ contacts to coens

A

invaginating

47
Q

On center bipolar cells act like a

A

classical inhibitory synapse

48
Q

What will cause a hyperpolarizing effect on a ON center bipolar cell

A

glutamte that is released then the OFF center cell is in dark and depolarized

49
Q

OFF center bipolar cell will ______ when light hits the center of our OFF center photoreceptor

A

hyperpolarize

50
Q

The OFF center bipolar cell is considered _______ to the OFF center cone it synapses with

A

sign conserving

51
Q

OFF center bipolar cells have _____ contact with OFF center photoreceptor

A

flat/basal

52
Q

OFF center bipolar cells have _____ receptors

A

ionotropic

53
Q

ON center bipolar cells ahve ______ receptor

A

metaborotropic

54
Q

What is the point of parallel pathways

A

improved sensitivity
one provides info about stimuli that are brighter than background (ON-center) while the other provides info on stimuli dimmer then background (OFF-center)

55
Q

Bipolar cells talk to

A
  1. Amacrine–for lateral connections
  2. Ganglion cells–to produce AP
  3. Parasol ganglions cells and midget ganglion cells
56
Q

large cells w/ large receptive fields, more transient and project to magno layers (only 10%)

A

parasol cells

57
Q

project to parvo layers, smaller cells w/ small receptive field and more sustained (make up 90%)

A

Midget ganglion cells

58
Q

Two parallel bipolar cells connect to

A

like minded ganglion cell (sign-conserving)

59
Q

Photoreceptors are completely synpaptically interconnected by an elaborate system of inhibitory interneurons called

A

horiozontal cells

60
Q

these guys laterally interconnect cones with other cones

A

horizontal cells

61
Q

every cone has a recipricol ______ synaptic relationship with all its neighbors

A

inhibitory

62
Q

When a cone is excited (depolarized) it _____ horizontal cells it synpases with

A

excites

63
Q

Excited horizontal cells will _______ neighbor cones via ______

A

inhibit

GABA

64
Q

the action of a depolarized horizontal cells is to

A

hyperpolarize the cones it synapses with

65
Q

The result of horiztonal cells is

A

enhanced edges

66
Q

Lateral inhibition gives us

A

imporoved resolution: increaes our ability to recognize edges

67
Q

Neurons responding to edge of a stimulus respond ______ then neurons responding to middle

A

more strongly

68
Q

Edge neurons recieve inhibition from neighbros on only one side, the side____

A

away from edge

69
Q

Neurons stimulated from the middle of a surface get:

A

inhibition from all sides

70
Q

Light falling in the region surrounding the photoreceptor, but not directly on it, turns the photoreceptor

A

ON

71
Q

What is our protein component of our rods

A

rhodopsin

72
Q

Rhodopsin mutations will alter _____ fnx

A

rod

73
Q

Rhodopsin mutations can

A

disrupt transport to OS, be retained in ER and affect stability of post-translation modification thus get constituitve activation

74
Q

characterized by progressive loss of rod and cone receptors with accompying vision loss

A

Retinitis pigmentosum

75
Q

Nighblindness is early symptoms with progressive constriction of visual field

A

RP

76
Q

Inheritence of RP

A

X-linked autosomal dom or recessive

77
Q

pigments that migrate from the RPE and adhere to blood vessels in RP will affect this first

A

rods

78
Q

most common form of deaf/blindness

A

Usher

79
Q

progressive vision/hearing loss, reduced odor identification, vestibular dysfuntion d/t motor proteins

A

Usher

80
Q

Usher is dt defects in

A

sensory cilia, core of sterocilical

81
Q 
Congenital defects are
\_\_\_\_ at birth
same/worse though life
can/cannot be classified easily
affects one or both eyes equally
A

present at brith
same through life
can be classified
both eyes equal

82
Q

visual aquity is often unaffected with confenital color vision defects: t/f

A

true

83
Q

congenital vision affects males or females more

A

males

84
Q

congentical color vision defects is usuallY;

A

protan or deutan

85
Q 
Aquired color vision:
Onset\_\_\_\_
type and severity\_\_\_\_\_
\_\_\_\_\_ differences occur
Visual acuity is \_\_\_\_\_\_
Predominately\_\_\_\_\_
affects males/females
A 
after birth
type and severity fluctuates
Monocular diff occur (not both eyes same)
reduced visual aquity
predom tritan
equal in male and female
86
Q

Achromoatopsia causes defect in:

A

CNG-betta, CNGA-3, GNAT2 (transducin)

87
Q

In achromatopsia cones:

A

cannot hyperpolarize in resposne to light

88
Q

affected ind w/ achromatopsia have:

A

no cone function

Med Neur 2 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions