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[13] [187] [188] Archaeplastids such as green and red algae eventually surpassed cyanobacteria as major primary producers on continental shelves near the end of the Neoproterozoic, but only with the Mesozoic (251–65 Ma) radiations of secondary photoautotrophs such as dinoflagellates, coccolithophorids and diatoms did primary production in ...
Cyanobacteria often live in colonial aggregates that can take a multitude of forms. [3] Of particular interest among the many species of cyanobacteria are those that live colonially in elongate hair-like structures, known as trichomes. These filamentous species can contain hundreds to thousands of cells. [3]
The organisms responsible for primary production are called primary producers or autotrophs. Most marine primary production is generated by a diverse collection of marine microorganisms called algae and cyanobacteria. Together these form the principal primary producers at the base of the ocean food chain and produce half of the world's oxygen ...
Marine microorganisms known as cyanobacteria first emerged in the oceans during the Precambrian era roughly 2 billion years ago. Over eons, the photosynthesis of marine microorganisms generated by oxygen has helped shape the chemical environment in the evolution of plants, animals and many other life forms.
Cyanobacteria usually obtain a fixed carbon (carbohydrate) by photosynthesis. The lack of water-splitting in photosystem II prevents heterocysts from performing photosynthesis, so the vegetative cells provide them with carbohydrates, which is thought to be sucrose. The fixed carbon and nitrogen sources are exchanged through channels between the ...
Marine cyanobacteria are to date the smallest known photosynthetic organisms; Prochlorococcus is the smallest at just 0.5 to 0.7 micrometres in diameter. [11] [2] The coccoid shaped cells are non-motile and free-living. Their small size and large surface-area-to-volume ratio, gives them an advantage in nutrient-poor water.
Oscillatoria are the subject of research into the natural production of butylated hydroxytoluene (BHT), [4] an antioxidant, food additive, and industrial chemical. Cyclic peptides called venturamides, which may have anti-malarial activity, have been isolated from bacteria in this genus. They are the first peptides with this activity to have ...
Cyanobionts provide benefit through dissolved organic carbon (DOC) production or nitrogen fixation but vary in function depending on their host. [12] Organisms that depend on cyanobacteria often live in nitrogen-limited, oligotrophic environments and can significantly alter marine composition leading to blooms .