What photopigment(s) are in cones?

• A. Rhodopsin
• B. Photopsin
• C. Cyanolabe, Chlorolabe, Erythrolabe
• D. Retinene

Answer: (C)

Cones use special photopigments called photopsins to detect different wavelengths of light. In humans there are three cone photopigments: cyanolabe, which is blue-sensitive; chlorolabe, green-sensitive; and erythrolabe, red-sensitive. These pigments enable color discrimination by responding to different parts of the spectrum and sending distinct signals to the brain. Rhodopsin, by contrast, is the pigment in rods and supports vision in dim light, not color vision in cones. Retinene is the retinal component that forms the chromophore part of these pigments, not a specific cone pigment. Photopsin is the general term for the cone pigment family, but the question asks for the actual cone pigments, which are cyanolabe, chlorolabe, and erythrolabe.