exam 3: vision Flashcards
where are the sensory receptors for humans (as well as most mammals)?
at the back of the eye, in the retina
where are the sensory receptors for birds?
on the tops of the eye
what is the wavelength range that humans are set up to see?
380nm - 750nm
t or f: the length of the wave is what our brain interprets as color
true
the place in the retina that gives humans the most focus, details, and acuity
fovea
represents only about 1% of the entire retina but the neurons in that part of the retina contain 50% of transfer through the optic nerve and 50% of the processing withing the visual cortex
fovea
where is the blind spot in humans?
where the optic nerve exits the eye because there are no more receptors
t or f: what isn’t picked up visually, the brain fills in so that you never realize when anything is missing out of your FOV
true
t or f: without receptors you don’t have vision
true
what are the three major layers of the retina that convert light waves into action potentials?
photoreceptors, bipolar cells, and ganglion cells
layer in the retina that is light-sensitive, consist of rod and cones and send info to bipolar cells
photoreceptors
what do rods detect?
light only (black/white)
what do cones detect?
color
layer in the retina that sends info to ganglion cells
bipolar cells
layer in the retina that have axons that form the optic nerve
ganglion cells
what are the two cells that allow parallel processing?
horizontal cells and amacrine cells
t or f: the only thing in our eyes sensitive to light waves are receptors
true
how many rods do our eyes have?
6-7 million
what photoreceptor is known as daylight vision?
cones
what photoreceptor is known as nighttime vision?
rods
what photoreceptor has less well-focused vision?
rods
what photoreceptor has the clearest vision at fovea and high acuity?
cones
what are the components of photoreceptors?
lamellae and photopigments (opsin, retinal, rhodopsin)
what are photopigments?
sensitive to light waves, three types: opsin, retinal, and rhodopsin
