A prokaryotic colony contains chlorophyll a, is surrounded by a gelatinous sheath and sometimes forms specialised nitrog
Cyanobacteria are photosynthetic prokaryotes containing chlorophyll a. Their colonies commonly possess a gelatinous sheath, and forms such as Nostoc and Anabaena may contain nitrogen-fixing heterocysts.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Protista - Chrysophytes and Dinoflagellates