vision Flashcards
wavelenght that we can respond but not see
UV and IR
choroid has
high conc. of blood vessels
sclera is the
eye white
fovea is the
most receptive part of the eye
function of fovea
produce visual info
what is the dioptic media
a light pathway
components of diopteric media
cornea, aq. fluid, lens and vitreous media
emmetropia
normal eyesight
ametropia
abnormal eyesight
types of ametropia
myopia, hyperopia, presobyopia, astigmatism
whats a snellen chart
eyesight chart for testing
whats an accommodation reflex
reflexes such as focusing length, iris size and lens size
retina contains
photoreceptors, neurons and pigmented epithelium
function of epithelium
provide nutrients, remove waste, set outer rod segment
rod function
brightness in the dark
cone function
brightness and color in the light
what is macula lutea
yellow surface around fovea
fovea centralis function
responsible for high-acuity visual
20 degrees (on the right eye)
blind spot since it is at the optic n, theres no rods or cones there
in the dark, the nerves are
depolarised
in the light, the nerves are
hyperpolarised
11 cis retinal occurs in the
dark
all trans retinal occurs in the
light
tranducsin is a
G protein
what does transducin activate
PDE
what does PDE do
hydrolyse cGMP to reduce its conc.
cGMP hydrolysis causes
Na+ channel to close
rhodopsin is made up of
retinal + opsin
what is amaurosis
vision loss not due by lesion
treatment for leber amaurosis
viral-based gene therapy (luxtura) via AAV
cone cells are photopigments and can tell apart what colors
red, green and blue
monochromats
grey scale
dichromats
green and blue
trichromats
green, blue and red
ishihara pseudoisochromatic
a test for color blind
is colorblindness hereditary
yes
achromatopsia condition
cant see colors
visual pathway
eye -> thalamus -> occipital
different pathway disruption
different blindness pattern
binocular vision is
the ability to combine and compare info from eye
binocular is the crossing of
optic fibers
