Physiology + Visual Pathway Flashcards
put in order from anterior to posterior: bipolar cell ganglion cell photoreceptor ganglion axon
ganglion axon
ganglion cell
bipolar cell
photoreceptor
what are amacrine and horizontal cells
lateral connections altering signal in transduction
what cells are responsible for transduction
photoreceptors
what are the two photoreceptors
rods and cones
which photoreceptors are responsible for seeing in dim light
rods
which photoreceptors are responsible for colour vision
cones
where is the highest concentration of cones
in fovea in macula
what is the rod pigment molecule
rhodopsin
what is retinal
vit A in pigment molecule
what type of receptor is involved in phototransduction
GPCR
where are rods located
peripherally on retina
which type of photoreceptor has low convergence
cones
which type of photoreceptor has 1 receptor:ganglion
cones
which type of photoreceptor has high convergence
rods
which type of photoreceptor is more prevalent
rods
which type of photoreceptor has many receptors:ganglion
rods
what is the role of cGMP in rod phototransduction
opens Na channel
what is phototransduction
converting electromagnetic radiation to neural signal
which type of photoreceptor has high acuity
rods
which type of photoreceptor has low light sensitivity
cones
which type of photoreceptor has low acuity
cones
which type of photoreceptor has high light sensitivity
rods
what are the types of cones
blue, green, red
what is the resting membrane potential of a photosensitive cell
depolarised
what happens to the membrane potential of a photosensitive cell on light exposure
hyperpolarises
what is hyperpolarisation
inside of cell becomes more negative
is the Na / K channel open in dark or light
open in dark
what is the ion movement when the Na / K channel is open
Na out of cell
K in cell
what structure transmits information from the eye to the optic chiasm
optic nerve
what happens to fibres from nasal fields at the optic chiasm
cross over
what happens to fibres from the temporal fields at the optic chiasm
continue ipsilaterally
what information is carried by the left optic tract
right visual field
what are binocular neurons
neurons in primary visual cortex that have input from both eyes for convergence
what immunoglobulins are present in tears
secretory IgA, IgG
what is MALT
mucosa associated lymphatic tissue
where is MALT
conjunctiva/lacrimal gland
what are the macrophages of the eye called
Langerhan macrophages
what is immune privelege
blood tissue barrier creates downregulated intraocular immune environment with no lymphatics and
is the corneal stroma hydrophobic or hydrophilic
hydrophilic
is the corneal epithelium hydrophobic or hydrophilic
hydrophobic
what topical routes can be used for the eye
drops and ointments
what is added to TOP CCS to make them hydrophobic
alcohol/acetate
what is added to TOP CCS to make them hydrophilic
phosphate
what drugs are given subtenons
local anaesthetics
what TOP local anaesthetic is used in the eye
proxymetacaine
what mydriatic drug is used for fundoscopy
tropicamide
what is the mechanism of tropicamide
blocks parasympathetic supply to iris to dilate pupil and stop the lens focusing
what are the side effects of tropicamide
stings, blurring, ACAG
what effect does atropine have on the pupil
dilates
