Phytochrome is a

Phytochromes are a class of photo receptors in plants. They are consist of proteins covalently linked to light sensing bilin – chromophore.So chemically they are chromoproteins. There is no sugar residue so can’t be glycoproteins. There is no Flavin derivative so can’t be flavoproteins & there is no lipid constituent so can’t be lipoproteins.