Vision SESE Flashcards
0
Q
Covers posterior surface of the eye lids and anterior surface of the sclera
- mucus membrane which serves as moist layer of epithelial tisue that has multiple functions or aborption and secretion
A
Conjunctiva
1
Q
Stimulus
Cranial nerve 2
Visual cortex
Vision
A
Transduction
2
Q
Formed by connective tissue and covers the posterior 5/6 of the globe
- continous with the dur matter
- perforated by many nerves and vessels passing through the posterior scleral foramen
A
Sclera
3
Q
Anterior structure and is composed of a circular diaphragm with a pupil
A
Iris
4
Q
Inner aspect contain of light that enters
A
Iris
5
Q
Inner aspect contain ciliary processes which secrete aqueous humor
A
Ciliary body
6
Q
Vascular layer
A
Choroid
7
Q
Sensory
- contains nerves is transparent
A
Retina
8
Q
Where the optic nerve exits iut of the eyeball, blind spot, no iion at this point
A
Optic disc
9
Q
Most sensitive spot wher the ones are concentrated
A
Macula
10
Q
An area of depression at the center of the macula
A
Fovea
11
Q
2 main blood suulies of the retina
A
Central retinal artery
Choroidal arteries
12
Q
Structure anterior to the lens and zonula
A
Anterior chamber
13
Q
All structures posterior to the lens and onula
A
Posterior chamber
14
Q
A crystalline structure that divides the anterior and posterior hamber
- biconvex
- covered by a capsule
- reponsible for the principle of accomodation
A
Lens
15
Q
Lens suspended from the ciliary bidy by fine delicate fibers called
A
Zonule or suspensory ligament
16
Q
Maintains sufficient pressure in the eyeball to keep ir distended
A
Fluid system of the eye
17
Q
Ciliary process mainly produce this
A
Aqueuos humor
18
Q
Component of aqueous humor
A
98.9% water
Protein, glucose, Na, K, Cl,
19
Q
Ascorbic osmotic pressure is higher than
A
Plasma
20
Q
Aqueous humor produced at ______ which should be matched by draining____ to maintain ______
A
2-3uL/ min
2.5uL/ min
10-20 mmHg IOP
21
Q
Clear gel that makes up about 80% of the eyes volume
A
Posterior
Vitreous humor
22
Q
Active secretion of Na involving ATP
A
Formation of aqueous humor
23
Q
Vitreous humor formed as an active secretionby the epthelium of the
A
Ciliary process
24
Vitreos humor secretions start with active transport of
Sodium ingo spaces between epithelial cells
25
Pull the cholride and bucarbonate ions cause osmosis of water from blood
Sodium ions
26
Flow of humor
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Pupil
Lens
Cornea and iris
Trabecular meshwork
Canal of schelm
```
27
Determined by the coupling of the production of aqueous humor
IOP
28
Drainage of the aqueous humor mainly through the
Trabecular meshwork
29
Eye conitions that lead to damage to the optic nerve
- IOP high
- tunnel vision
Glaucoma
30
Patho of glauoma
Scleral sinus is blocked
Pressure in the anterior and posterior chambers
Vitreous body presses the retina against the choroid and compresses the blood vessels that feed the retina
31
Visible spectrum
380-760
32
Bending of wave when it enters a meium at an angulatedbangle
Refraction
33
If light rays travels to an angulated surface,
Refraction of the ray will also occur
34
Speed light is altered by a change in the
Optical medium
35
Kapag tumagos taos yung light
The rays enter without deviating from their course.
| The only effect that occurs is decreased velocity of transmission
36
Ratio of the speed of light in the air to a speed of light to a substance
Refractive index
37
Example of convex lens
- all the light rays are bent towards the center
-
Convex lens
Converging
Thicker middle
38
The nearer the light rays to the center
Smaller theangulation that each create
39
Light rays that enters the convex lens at the center is
Not refracted
40
All the light rays are bent away fom the center,
Concave lens
Diverging
Thinner middle
41
The pupil can change its size and the lens can change its curvature forming an image on the retina
In the eye
42
Light rays coming from an object passes through the shutter to form an image on film
In a camera
43
When all the refractive surfaces of the eye are added together and considered as one lens
Reduced eye
44
Greater a lens bends light rays, the greater the referactive power which is measured in
Diopters
45
Power lens
1/f
46
Distance from lens to area where the light rys converge
F- focal length
47
Greater refractive power
Smaller focal length
48
Toral refractive power
59 diopters
49
2/3 refractive power of the eye
Cornea 1.38
50
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Vitreous humor
Lens
Aqueous humor
Cornea
Air
```
1. 34
1. 40
1. 33
1. 38
1. 00
51
Which part of the eye has the greatest refractive power?
Cornea
52
Significant refractive power
Aq humor
Lens
Vit humor
53
Power of lens is only
20 diopters
54
Lens accomodation
Up to 34 diopters
55
Elastic, filled with transparent fluid
Lens
56
Pull on lens and make it less convex
Suspensory ligaments
57
Subkects can focus on near objects because of
Increase in focal power
58
When you pull zonule fibers, mking the lens
More convex
59
Kapag near focus ang lens
Hinihila ng zonule fibers at ciliary muscles
60
From original of 20 diopters can be increased to
34 diopters in children
61
This ability decreases as we ge
14D up to 40 years
2D at 40-50 years
0D at 70 years
62
Occurs in elderly due to inability of lens to accommodate.
Double vista
Presbyopia
63
Degree to which the details and contours of objects are perceived
Visual acuity
64
2 lines can be separated and still be perceived as
2 lines
65
Visual acuity, clinically ecaluated using
Snellen chart
66
describes the state of vision where an object at infinity is in sharp focus with the eye lens in a neutral or relaxed state
Emmetropia
67
Distant objects are in sharp focus on the retina
Relaxed ciliary muscle
68
Near objects are in sharp focus to the retina.
| Parasympathetic innervation
Contracted cilary muscle
69
Far sightedness
| Image s focused behind the retina
Hyperopia/hypermetropia
70
Correction of hyperopia
Converging lens + D lenses ( convex)
71
Nearsightedness
Far objects focused in front of retina
Lens with too much refractive power eyeball too long
Myopia
72
Correction of myopia
Diverging lens D- lenses ( concave)
73
Too great a curvature of the cornea in one plane of the eye, spherical aberation where you have multiple focal points
Astigmatism
74
Generally narrower and longer
| Low visual acuity
Rods
75
Foveal region, narrow and long
| High visual acuity
Cones
76
Photosensitive chemical
| Color pigment
Rhodopsin
77
Where discs of cell membranes are found contain rhodopsin and color pigments
Outer segment
78
Cytoplasmic organelles
Inner segment
79
Connected to neurons
Synaptic body
80
Molecule responsible for its color
Opsin protein
| Chromophore
81
These pigments are sensitive to light and are composed of an OPSIN protein and a carotenoid pigment called
11 cis retinal
82
Only form that can bind rhodopsin
Cis
83
Rhodopsin
| Scotopsin
Rods
84
Color pigment
| Photopsin
Cones
85
Allows you to bind scotopsin properly
11 cis retinal
86
Photosensitive chemical
Opsin protein retinal
87
When light is absorbed by rhodopsin
```
Decomposition
Barthorhodopsin
Lumirhodopsin
Metarhodopsin I
Metarhoopsin II
```
88
Begins the neural activity
| Electrical changes transmit the visual image into the CNS as an action potential
Metarhodopsin II
89
Pathway 1
All trans retinal
Retinal isomerase
11 cis retinal
90
Pathway 2
All trans retinol
Isomerase
11 cis retinol
11 is retinal
91
Hyperpolarization
| Increase negativity of membrane due to decrease permeability to Na+
Exitation of Rods
92
Pumps Na out
Inner segment
93
Leaky to Na
Outer segment
94
More negative
Rhodopsin decomposes- metarhodopsin II
Basta lumalabas yung sodium outer and inner
Hyperpolarizing
95
Non gated channels
| Net effect potential
K in the cell
96
CGMP dependent on the absence or presence of light
Dark state
Light state
Leaky
| Closed
97
Vitamin A role in formation of Rhodopsin
Cytoplasm
For new retinal
Excess retnal back to Vit. A
98
Vitamin A deficiency
Night blindness
99
Layers of retina
INGIIOOEPR
100
Contains amocrine cells
Inner plexiform
101
Contains horizontal cells
Outer plexiform
102
Rods and cones which are photosensitive cells that convert chemical energy into electrical energy
Receptor cells
103
Mechanism for lateral inhibition
| High visual accuracy in transmitting contrast borders in the visual image
Horizontal cell
104
Vertical direction
| From rods, cones and horizontal cells to the ganglion and amacrine cells
Bipolar cells
105
Contra palagi ang bipolar cells at horizontal cells
Must know
106
Interneurons that analyze visual signals before they leave retina
Amacrine cells
107
Bipolar to ganglion cell
Vertical amacrine
108
Within the inner plexiform layer
Horizontal amacrine
109
Differentiates a steady light, a flickering light, on and off light
Change in illumination
110
Axons generate to the optic nerve
| Send repetitive action potentials to the CNS
Ganglion cells
111
The rest of the retinal cells conduct their visual signals via
Electronic conduction
| Voltage dependent conduction
