title: EPR evidence for an acceptor functioning in photosystem II when the pheophytin acceptor is reduced.
mesh_terms: D002734:Chlorophyll / Q000031:analogs & derivatives*; D002736:Chloroplasts / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D010084:Oxidation-Reduction; D010674:Pheophytins / Q000378:metabolism*; D010785:Photophosphorylation; D010944:Plants / Q000378:metabolism
chemical_list: D010674:Pheophytins; D002734:Chlorophyll