Difference in the degree of exposure of chromophores in the Pr and Pfr forms of phytochrome.
D003624:Darkness; D007700:Kinetics; D008027:Light; D010084:Oxidation-Reduction; D010834:Phytochrome / Q000302:isolation & purification; D010940:Plant Proteins / Q000302:isolation & purification; D010944:Plants / Q000032:analysis; D013053:Spectrophotometry
D010940:Plant Proteins; D010834:Phytochrome