two cation-specific sites have been found in photosystem ii : one on the 3- ( 3,4-dichlorophenyl ) -1 , 1-dimethylurea-insensitive silicomolybdate pathway , which responds better to restoration by mg ( 2+ ) than by ca ( 2+ ) ions , the other on the forward pathway to photosystem i , located on the 2,5-dimethylbenzoquinone pathway .
C0007447
cation
C0022023
ions