exam 2 Flashcards
color of sensory retina
clear
what is the horizontal line of raphe
invisible line goes through macula
arteries vs veins
veins thick and dark
arteries thinner and lighter
what cell is very metabolically active what shape are they
RPE
polyhedral pigmented cuboidal and columnar epithelial ells
amount of rods & cones in
macular
periphery
macula - cones
periphery rods>cones
1/3 DD is ______ microns
average disc diameter is
500 microns
1.4-1.22 mm
name the different dimensions of the macula in order of smallest to largest diameter
which one has
-high number of ganglion cells and bipolar cells
-avascular zone
-rod free zone
foveola - rod free
fovea - avascular zone
parafovea - ganglion and bipolar cells
perifovea
the fovea is the location of foveal avascular zone. It instead gets its supplies from
choriocapillaries
what supplies
inner 2/3 of retina
outer 1/3 of retina
inner is - central retinal arter
out is - choroid
name the 3 order of cells in retina
- photoreceptor
- bipolar (inner nuclear layer)
- ganglion
what layer is the bipolar cells located
inner nuclear layer
how many photo receptors does one RPE cell interact with
1 rpe for 30-40 photoreceptors
what connects the outter and inner seg of rods and cones
cilium
what is in the myoid region and ellipsoid region of the rods and cones
myoid
-makes proteins golgi and ER
Ellipsoid region
-makes energy has mitochondria
what region of the photoreceptors have discs
where region connects to rpe cells
out regions
outer region
what is spherules and pedicles
synaptic terminals
spherules - rods
pedicles- cones
what part of the photoreceptors shed constantly
what eats this
discs of outer segment
rpe cells
where is the location where alot rods are located at
3 mm from the center of fovea
what is rhodopsin
pigment of rods
where are photo pigments produced
inner segment then move to discs
name the two components of pigments
what is the purpose of each
which is located in the discs
-chromophore (retina)
absorbs light same in all
-opsin (protein
responsible for wavelength sensitivity
interlaced with discs
metarhodopsin 2 activated what
transducin in photo transduction
GTP and alpha subunit activates what
PDE phosphodiesterase
what percent of people have color deficiency
4.5%
what is the dz of enlarged RPE cells
packed melanin granules
CHRPE
congenital hypertrophy of retinal pigment epithelium
what dz is linked to colon cancer
CHRPE
what dz has apparent bone spicules
what is spicules what other signs
retinitis pigmentosa
bone spicules are peripheral pigment clumping of spicules
stenuated BV waxy pallor of ONH
cystoid macular edema
ELM is in between what cells
what does the ELM do
mullers and photoreceptors
photoreceptor nuclei and inner segments
it restricts movement of large molecules
the outer nuclear layer contains what cell bodies
rod and ones body
describe the outer plexiform layer OPL
synaptic layer where photo receptors connect to bipolar cells
photoreceptors produce what kind of potentials
graded potentiantial
what layer separates the inner and outer retina
outer plexiform
what marks the extent of the retina
invisible divide of the retina
middle limitting membrane
What synaptic shape has gap junctions
Pedicles
Name the two capillary networks and where they are located
- Deep - inner nuclear layer
- Superficial- RNFL
Horizontal cells
-Number of axons
-number of dendrites
-synapse with
-gap junctions?
-depolarize when
-graded or action potential
-type of neurotransmitter
Horizontal cells
-Number of axons
1 axon and multiple dendrites
-synapse with
Other horizontal cells
Photoreceptors
Bipolar
For inhibitory effect
-gap junctions?
Yes
-depolarize when
In the dark
-graded or action potential
Graded
-type of neurotransmitter
Gaba
Which cell provides lateral inhibition ? To what cells
Horizontal cells to photo receptors and bipolar cells
Name the three different photo pigments in cones and what their maximum absorbance is
Cyanolabe - 420 nm
Chromolabe - 531 nm
Erythrolabe- 588nm
what is rhodopson composed of where is it located
opsin and 11 cis retinAL out sigment in discs
chromophor or opsin
derivitive of vit a
responsible for wave lenght sensitivity
g coupled
same in all
derivitive of vit a - chromophor
responsible for wave lenghth- opsin
g coupled- opsin
same in all - chromophor
phototransduction induces or spresses release of glutamate
supresses
describe the renewal system
light reacts with rhodopsin where it isomerized 11cisretinal to all trans retinal. It then disociates from rhodopsin where it is then reduced to all trans retINOL. Its transfered to RPE cells where it can then be turned into 11 cisretinal
in the dark Rhodopsin is active or inactive
does this cause hyperpolarization or depolarization
in active. RHODOPSIN ONLY ACTIVE IN LIGHT
depolorization
what channel is a ligand gated channel in phototransduction
what is its ligand
calcium
cGMP
dot blot heme occurs where
inner nuclear layer and out plexiorm layer
inner nuclear layer holds what cell bodies
horizonatal
bipolar a
amarcrin
interplexiform
mulers
basically all but photo and rpe
what cell synaps with amacrine 2 cells
when do they deporize
in the light
rod bipolar
amacrineII connects rod bipolar with ganglion
amacrine release what neurotransmitter
glycerine and gaba
there are two important inhibitory cells what are they and what feedback or feedforward mechanisms do they affect
amacrine- feed back bipolar
- feed forward ganglion
horizontal cells- feed back - photorecptors
feed forward biopolar
which two cells are action potential
amacrine
ganglion
amacrine send infor horizontally or vertically
how many processes does it have
both
has single process
what inhibitory cell connects to interplexifomr cells
amacrin
what cell sends infor from photoreceptor to ganglion cell
bipolar
in the fovea a bipolar midget cell connects to ____ cone(s) while in the periphery it connects to ____cones
what about if it were rod bipolar?
1 cone
2-3
no rodbipolar in fovea
15-20 rods centrally
80 peripherally
what cell forms triads
what is part of the triad
invaginating midget bipolar
2 horizontal cells 1 invaginating midget
diffuse cone bipolar cells connect to ____ cones centrally and _______ peripherally
diffuse cone bipolar cells connect to __5__ cones centrally and ___10-15____ peripherally
what bipolar cells has the largest dendritic trees
giant cone three trees then clusters types
diffuse and then bistratified
blue cone bipolar cells connect what
widely spaced blue cones
what cell is known to have a large cell body
where is it located
interplexiform cells
OPL
IPL
what is ionotropic receptor
what is metabotropic receptor
receptors of bipolar cells that shows if they are on or off
ionotripic is off
metabotropic is on
in the central retina 1 cone is connected to what an off or on bipolar cells
1 one and one off
what layer does bipolor synapse with ganglion
whos processes are found here
inner plexiform layer
amacrine interplexifprm processes
what dz is associated with flame heme
vein occlusion
what layers are muller cells found
ilm to elm cell bodies in ilm
what cell has a high oxyen consumption
photoreceptors
ribon synapse purpose
allows for constant release of glutamate
retinoscnisis location and what is it
splite of retina in the outer plexiform
what disease looks like fishnet stocking
reticular degeneration coneycomb degeration usually pigment finding in periphery in old patients no clinical significance
what layers do the photoreceptors span to
2-5
