Bacteria are prokaryotic and lack membrane bound cell organelles like mitochondria, chloroplast, nucleus etc. The photosynthetic bacteria contain bacteriochlorophyll but chlorophyll-a is absent. They use inorganic electron donor like H2S,H2 , sulphur compound etc. Algae are eukaryotic (except blue-green algae) They contain the lamellae in the cytoplasm and lack well organised chloroplast. The Characteristic chlorophyll pigments are : Blue green algae-Chlorophyll a, phycocyanin. Green algae-Chlorophyll-a, chl. b, Brown algae-Chlorophyll-a, chl. c, Red algae-Chlorophyll-a, chl. d, phycoerythrin.