A

David

Darling

retinal

11-cis-retinal

Rhodopsin comprises a species specific protein, opsin, conjugated with the 11-cis-isomer of retinal. On bleaching in light, the retinal is released as the all-trans-isomer.


Retinal is the key molecule involved in vision. It is a crystalline pigment, C19H27CHO, and a component of rhodopsin. Also called retinene, it is the aldehyde of vitamin A.