Colour Vision

Question 1

What is wavelength

Answer 1

The distance from one wave peak to the next

Question 2

How do colors differ from one another

Answer 2

By their different wavelengths

Question 3

What is the wavelength range that we can typically see

Answer 3

400nm (violet) to 700nm (red)

Question 4

Why can we see these specific wavelength peaks from an evolutionary standpoint

Answer 4

Because the sun peaks there too and the earth’s atmosphere is transparent to these wavelengths

Question 5

What wavelength is sea water most transparent at when eyes first evolved

Answer 5

Less than 500nm

Question 6

What is the color cone percentage breakdown for human eyes

Answer 6

Red: 63%
Green: 31 %
Blue: 6%

Question 7

Why are we called trichromatic

Answer 7

Because we see color with three types of cones

Question 8

What wavelength color does rhodopsin prefer

Answer 8

Blue-green

Question 9

What wavelength color does melanopsin prefer

Answer 9

Blue

Question 10

What happens when your red cones are hyperpolarized? Why

Answer 10

When your red cones are hyperpolarized, your blue ones will not be and you will perceive yellow. This is because yellow light affects red and green cones

Question 11

Primary colors

Answer 11

Red, blue, and green

Question 12

Spectral colors

Answer 12

Colors that can be evoked by light of a single wavelength. Include rainbow colors

Question 13

Extraspectral colors

Answer 13

Colors that are evoked from the 2 or more wavelengths mixed together.
Purple is an example because the wavelengths affect red and blue cones more than green ones

Question 14

Fill in the blank.

Ganglion cell color signals are combinations of ________________.

Answer 14

Cone signals

Question 15

R+G cells

Answer 15

Ganglion cells are excited by red and green light.
Aka yellow channel

Question 16

R-G cells

Answer 16

Ganglion cells that are excited by red light and inhibited by green.

Question 17

G-R cells

Answer 17

Ganglion cells inhibited by red light and excited by green light

Question 18

What is the name of the R-G and G-R phenomenon

Answer 18

Red-green opponent channel

Question 19

B-R-G

Answer 19

Cells excited by blue light and inhibited by red and green

Question 20

blue-yellow opponent channel

Answer 20

B-R-G and B-R+G (blue minus yellow)

Question 21

How can opponent channels explain afterimages

Answer 21

Your G-R cells (for example) fatigue and are less active, leaving R-G’s more active

Question 22

What is the most common color-blind variant

Answer 22

Red-green colour blindness (daltonism)

Question 23

Why are men affected more by colour blindness

Answer 23

Because the Red-Green variant lies in the X chromosome.
for females, if one X chromosome codes a fault pigment, the other X can compensate.

Question 24

Reflectance

Answer 24

Surface’s tendency to reflect certain wavelengths of light and absorb others

Question 25

What does the light an object sends to our eyes depend on?

Answer 25

Reflectance and illumination