iClicker Module 7 Flashcards
In theatre, they use gels to cover the lights to change their hue. What wavelength of light would pass through a blue gel creating a blue spotlight?
Only blue light (400-475 nm)
If I stole all of the theatre lights and used a different gel on each one and pointed them all to the center of the stage what color would the spot be?
White
Yes or No: Some people have corneas that are more rounded while others have corneas that are more oblong (football shape). Does this difference in curvature influence their visual acuity?
Yes
When you go to the ophthalmologist, they may put drops in your eyes so they can look at the back of your eye (also called a fundus). Why do they suggest you wear sunglasses afterward?
Because the drops dilated your pupils allowing too much light into your eye
Which structures influences the path of light before it hits the retina?
Cornea
Aqueous Humor
Lens
Vitreous Humor
What would happen to your vision if your unaccommodated lens caused the light to focus PAST the retina?
Farsightedness (can’t see up close)
Why do people squint when they have a hard time seeing something?
Squinting can change the shape of your eye
-Force your eye to be more oblong (less round)
If the crystalline structure of the lens becomes disrupted, it becomes opaque (less transparent). How would this influence your vision?
It would make everything harder to see
Light travels through which part of the eye first?
Cornea
Which photoreceptors are specialized for low light situations?
Rod
Which form of electromagnetic radiation causes skin cancer AND can be detected by insects?
UV light
Which area of the retina has the highest concentration of cone photoreceptors?
Fovea
Each cone photoreceptor has a different opsin. Red cone photoreceptors do what?
Transduce red light
Which of the following statements is false about the transduction of light?
-Light stimulates the opsin
-Secondary messenger cascade triggers hyper polarization by closing sodium channels
-Retinal opens sodium channels depolarizing the neuron
-The amount of neurotransmitter released is proportional to the amount of photons detected
Retinal opens sodium channels depolarizing the neuron
Which retinal cell type is important in lateral inhibition?
Horizontal cell
Which retinal cell type transduces light?
Photoreceptor
Which retinal cell sends information to the brain via the optic nerve?
Ganglion cell
What cell type of cell pools information allowing your visual system to be more sensitive?
Diffuse Bipolar cell
Within the fovea, each cone photoreceptor synapses with…
both on & off bipolar cells
Within the fovea, each midget bipolar cell synapses with how many and what kind of ganglion cell?
A single P ganglion cell
What is the function of an amacrine cell?
The precise function is unclear
Which type of ganglion cell makes a larger contribution to visual acuity (smallest spatial detail that you can see)?
P ganglion cells
If light hit the periphery of the receptive field of an ON-center ganglion cell. What would happen to its firing rate?
Decrease
If the light hit the center of the receptive field of an ON-center ganglion cell. What would happen to its firing rate?
Increase
Yes or No: Is your ability to perceive spatial details better if you look at it with your peripheral vision?
No
Your fovea has the most number of cones
Coming into one input, making peripheral bad compared to center
How would an on-center ganglion cell of respond (relative to any other time with the moving bars) when the light is only in the center?
Increase in firing rate
(positive response)
How would an on-center ganglion cell of respond (relative to any other time with the moving bars) when the light is only in the periphery?
Decrease in firing rate
(negative response)
How would an on-center ganglion cell of respond (relative to any other time with the moving bars) when the light is between center and periphery?
No change/ in the middle
(no response)