Transformation into the zygote, or hypnoblast, is characterized by the production and accumulation of reserve materials that include sugars and lipids as well as the formation of esterified secondary carotenoids. The secondary carotenoids will turn the green zygotes orange as they accumulate in the area around the plastids of the cell to protect the zygotes from UV radiation.
Transformation into a zygote, or hypnoblast, is characterized by the synthesis and storage of energy-rich compounds such as sugars and lipids, along with the formation of protective pigments called secondary carotenoids. As these pigments accumulate near the plastids in the cell, they impart an orange color to the green zygotes, protecting them from UV radiation.