Also known as blue-green algae, cyanobacteria are single-celled microorganismsMicroorganisms are living beings that cannot be seen with the naked eye. ‘Micro’ is a prefix tha capable of producing energy via photosynthesisPhotosynthesis is the biological process by which light energy, usually from the sun, is converted t and are widely distributed in aquatic habitats. Even though this group is known as blue-green algae it is different from algae and falls within the bacteria kingdom.