Vision I Flashcards
How many layers does the retina have?
Three
How many cell types does the retina have?
Five
Function of the retina?
Transduction and transmission
What are the three layers of the retina?
Outer nuclear layer (ONL), inner nuclear layer (INL), ganglion cell layer (GCL)
What are the cell types present in the retina?
Photoreceptor, bipolar cell, ganglion cell, amacrine cell, horizontal cell
Photoreceptors can be divided into:
Rods and cones
Function of rods?
Black and white vision, movement
Function of cones?
Color vision
Subtypes of cones?
short-wave (blue), medium-wave (green), long-wave (red)
Function of photoreceptors?
Release glutamate to inhibit bipolar cells
The fovea has no [insert word] and a high density of [insert word].
Rods, cones
The fovea is a blind spot in [insert word] conditions.
Dim-lighted (scotopic)
True or False?
Rods are slower to respond than cones.
True
True or false?
Rods require 100 photons to activate.
False
Cones require 100 photons to activate while rods only require one.
One ganglion requires [insert word] rods and [insert word] cones.
Many, few
True or False?
Rods are more sensitive to blue/green than red.
True
Which chromosome are L and M cone opsins encoded on?
The X chromosome
True or False?
Sensitivity curves differ across species.
True
Why does the military use red at night to study maps?
Rods are insensitive to red light and protects night vision.
Rods and cones both [insert word] in response to light while they [insert word] in the dark.
hyperpolarize, depolarize
[insert word] channels are open in the dark, allowing inward ion current.
Sodium (Na+)
Retino-geniculo pathway
Retina, lateral geniculate nucleus (LGN), visual cortex (dorsal and ventral stream)
Secondary pathway
Retina, superior colliculus, parietal lobe
Optic chiasm
Spot where some axons cross hemispheres
Optic nerve
Axons of retinal ganglion cells
Where does the LGN (thalamus) receive information from contralateral visual field from?
Both eyes
Where do LGN neurons project to?
Striate cortex (V1)
