Photopsin

Photopsin refers to the opsin of the cones . Cones are receptors , or sensory cells, in the retina of animals (including humans).

A common synonymous term for photopsin is cone opsin . Photopsin is a necessary, but not sufficient, component of those visual pigments that enable photopic vision in at least good lighting conditions . Color perception is achieved by calculating the excitations of different receptors, which have their absorption maxima at different wavelengths of light. The visual pigments that are formed by photopsin are called iodopsin if they contain retinal 1 as chromophore and cyanopsin if they contain retinal 2. Animals living on land and marine fish form their visual pigments exclusively with retinal 1. Freshwater fish and many amphibians can also form visual pigments with retinal 2. In contrast to most terms that end in the word -opsin , photopsin clearly and exclusively means the protein content of a visual pigment and not the entire pigment, including retinal. The article Opsin contains a rough overview of the most common terms that end in the word -opsin .

See also

Rhodopsin , the visual pigment of the rods.

credentials

1. ↑ George Wald, Paul K. Brown, and Patricia H. Smith in The Journal of General Physiology , Vol 38, 623-681, 1955 (abstract) .