. "The chemical reactions and pathways resulting in the formation of apocarotenoids by the oxidative cleavage of carotenoids. Many apocarotenoids are biologically important e.g. retinal and abscisic acid." . . . "apocarotenoid biosynthetic process" . "apo carotenoid biosynthetic process" . "apocarotenoid anabolism" . "apocarotenoid biosynthesis" . "apocarotenoid formation" . "apocarotenoid synthesis" . . .