Functioning of the Cones

Question 1

What pigment is found in cones and how many forms does it have with what function?

Answer 1

Iodopsin; 3 different forms.

Each of the three forms occurs in different cones and absorbs light of a different wavelength.

Question 2

Each of the three forms occurs in different cones and absorbs light of a different wavelength, giving rise to what?

Answer 2

Giving rise to ‘red’, ‘green’ and ‘blue’ cones which are most sensitive to these wavelengths of light.

This is called the trichromacy theory of colour vision.

Question 3

Iodopsin is not so easily ____ so what is required? It also ____

Answer 3

“broken down”
Bright light.
“regenerates more slowly.”

Question 4

How are different colours detected by the brain?

Answer 4

Different wavelengths stimulate different cones and the combined information reaching the brain produces the final colour detected.