Marine microorganisms are defined by their habitat as microorganisms living in a marine environment, that is, in the saltwater of a sea or ocean or the brackish water of a coastal estuary. A microorga
Role of the microbial community in the marine carbon cycle
Microbial mats are the earliest form of life on Earth for which there is good fossil evidence. The image shows a cyanobacterial-algal mat.
Stromatolites are formed from microbial mats as microbes slowly move upwards to avoid being smothered by sediment.
Relative sizes of microscopic entities
Cyanobacteria are a group of autotrophic gram-negative bacteria of the phylum Cyanobacteriota that can obtain biological energy via oxygenic photosynthesis. Cyanobacteria originated in a freshwater or
Cyanobacteria are found almost everywhere. Sea spray containing marine microorganisms, including cyanobacteria, can be swept high into the atmosphere where they become aeroplankton, and can travel the globe before falling back to earth.
Prochlorococcus, an influential marine cyanobacterium which produces much of the world's oxygen
Unicellular and colonial cyanobacteria. (scale bars about 10 μm)