cis-retinal
cis-retinal
(sĭs′rĕt′ĭ-năl, rĕt″năl) [L. prefix cis-, this side of + ″]The form of retinal combined with a glycoprotein opsin (rhodopsin in rods) during darkness. Light striking the retina changes it to trans-retinal and begins the generation of a nerve impulse.
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