Vision 1 Flashcards
This type of spherical lens will converge light rays
Convex
This type of spherical lens will diverge the light rays
Concave
This type of lens will give you a focal line
Cylindrical
If you increase the power of the lens, it will give you what kind of focal length
Shorter focal length
Power of the lens is determined by what unit
Diopter
Refractive power of spherical convex lens will give you
A positive power
If you have 10 diopter, the focal point is
Nearer to the lens
It can dilate and constrict to control how much light can enter
Pupil
This is where the object will be registered
Retina
Is has the highest capability of bending light rays or highest refractive power
Cornea
This holds the lens to maintain its shape
Suspensory ligament
What happens if the suspensory ligament is tight or tense
It would decrease the convexity
Decrease the power of the lens
If the ciliary muscles contracts what will happen to the lens
The lens would be more convex
Increase the power of the lens
This condition is called loss of accommodation by the lens
Presbyopia
Normal vision is called
Emmetropia
Causes of hyperopia
Weak lens
Small eyeballs
What lenses do you give when the px has hyperopia
Convex
Causes of myopia
Growing eyeballs
Increases thickness of the lens
What type of lens do you give to px with myopia
Concave
This condition has an irregular shaped cornea
Keratoconus
The part of the retina has highest visual acuity
Fovea centralis
In depth perception, the person perceives 3 majors means
Size of the image of known object
Moving parallax
Stereopsis
The perfect vision is said to be what in meters
6meters by 6 meters
Which organ secretes aqueous humor
Ciliary process
Where does the aqueous humor drain
Canal of schlemm
What are the reasons of increased intraocular pressure
Blockage of the canal of schlemm
Old age (fibrotic canal)
What are the photoreceptors of the eyes
Rods and cones
This is responsible for vision at low light levels (scotopic vision)
Rods
Responsible for color vision and responds well to bright light (photopic vision)
Cones
Besides the horizontal cells, what other cells can perform lateral inhibition
Amacrin
Bipolar cells
Rhodopsin or visual purple is for what
Rods
Black and white
Cone pigments or color pigments are for what
for the cones
For color vision
Metarhodopsin 2 is also known as and it is broken down into what
The activated rhodopsin
Scotopsin and all trans retinal
What happens there is a high cGMP
Sodium influx
