Vision Flashcards
(17 cards)
Photons reflect off which area of the retina? Why?
Photons reflect off the back of the retina so that it hits the rods and cones first.
(rods/cones) respond to low light.
Rods
(rods/cones) respond to medium light and moonlight.
Rods and cones
(rods/cones) responds to bright lights.
Rods
Photoreceptors release glutamate in __________ (light).
Darkness
Photoreceptors exhibit graded ________________ in response to different levels of light.
Hyperpolarizations
What are the 3 types of ganglion cells?
- Parvocellular-X
- Magnocellular-Y
- Koniocellular
Are bipolar cells excited or inhibited by photoreceptors?
Both! They are bipolar!
Bipolar cells exhibit graded ________ potentials.
Electical
On-bipolar cells ______polarize in response to glutamate.
Hyperpolarize
Off-bipolar cells ________polarize in response to glutamate.
Depolarize
Type I ganglion cells respond to…?
A light spot in an otherwise dark field
Type II ganglion cells respond to…?
A dark spot in an otherwise illuminated field
When a light spot is detected in a dark field, the ON-bipolar cells ______polarizes, causing the Type I ON-ganglion cell to be __________.
On-bipolar cell hyperpolarizes = Type I ON-ganglion cell to be excited
When a light spot is detected in a dark field, the OFF-bipolar cells ______polarizes, causing the Type I OFF-ganglion cell to be __________.
Off-bipolar cell depolarizes = Type I Off-ganglion cell to be inhibited
When a dark spot in an otherwise illuminated field is detected the ON-bipolar cells ________polarize, causing the Type II ON-ganglion cell to be ________ by the lack of light.
On-bipolar cell depolarizes = Type II on-ganglion cell to be inhibited
When a dark spot in an otherwise illuminated field is detected the OFF-bipolar cells ________polarize, causing the Type II OFF-ganglion cell to be ________ by the lack of light.
Off-bipolar cell hyperpolarizes = Type II off-ganglion cell to be excited
