Cyanobacteria facts for kids
Quick facts for kids CyanobacteriaTemporal range: 3500 mya – Recent
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Cyanobacteria
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The taxonomy is under revision
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Cyanobacteria are a taxon of bacteria which conduct photosynthesis. They are not algae, though they were once called blue-green algae. It is a phylum of bacteria, with about 1500 species. In endosymbiont theory, chloroplasts (plastids) are descended from cyanobacteria. Their DNA profile is evidence for this.
Cyanobacteria have an extremely long fossil record, starting at least 3,500 million years ago. They were the main organisms in the stromatolites of the Archaean and Proterozoic eons.
The ability of cyanobacteria to perform oxygenic photosynthesis is highly significant. The early atmosphere on Earth was largely reducing, that is, without oxygen. The cyanobacteria in stromatolites were the first known organisms to photosynthesise and produce free oxygen. After about a billion years, the effect of this photosynthesis began a huge change in the atmosphere. The process, called the Great Oxygenation Event, took a long time. Eventually, it killed off most of the organisms which could not live in oxygen, and led to the kinds of environment we know today, where most organisms use and need oxygen.
Light detection
Cyanobacteria have a way of detecting light. Conrad Mullineaux, of Queen Mary University of London, said, "It has a way of detecting where the light is; we know that because of the direction that it moves".
- "In a single-celled pond slime, they observed how incoming rays are bent by the bug's spherical surface and focused in a spot on the far side of the cell. By shuffling along in the opposite direction to that bright spot, the microbe moves towards the light".
Related pages
Images for kids
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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.
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Prochlorococcus, an influential marine cyanobacterium which produces much of the world's oxygen -
Morphological variations • Unicellular: (a) Synechocystis and (b) Synechococcus elongatus • Non-heterocytous: (c) Arthrospira maxima,(d) Trichodesmium and (e) Phormidium • False- or non-branching heterocytous: (f) Nostocand (g) Brasilonema octagenarum • True-branching heterocytous: (h) Stigonema(ak) akinetes (fb) false branching (tb) true branching -
Nitrogen-fixing cyanobacteria -
Cyanobacterial thylakoid membrane Outer and plasma membranes are in blue, thylakoid membranes in gold, glycogen granules in cyan, carboxysomes (C) in green, and a large dense polyphosphate granule (G) in pink -
Environmental impact of cyanobacteria and other photosynthetic microorganisms in aquatic systems. Different classes of photosynthetic microorganisms are found in aquatic and marine environments where they form the base of healthy food webs and participate in symbioses with other organisms. However, shifting environmental conditions can result in community dysbiosis, where the growth of opportunistic species can lead to harmful blooms and toxin production with negative consequences to human health, livestock and fish stocks. Positive interactions are indicated by arrows; negative interactions are indicated by closed circles on the ecological model.
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Diagnostic Drawing: Cyanobacteria associated with tufa: Microcoleus vaginatus
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Symbiosis with land plants Leaf and root colonization by cyanobacteria (1) Cyanobacteria enter the leaf tissue through the stomata and colonize the intercellular space, forming a cyanobacterial loop. (2) On the root surface, cyanobacteria exhibit two types of colonization pattern; in the root hair, filaments of Anabaena and Nostoc species form loose colonies, and in the restricted zone on the root surface, specific Nostoc species form cyanobacterial colonies. (3) Co-inoculation with 2,4-D and Nostoc spp. increases para-nodule formation and nitrogen fixation. A large number of Nostoc spp. isolates colonize the root endosphere and form para-nodules. -
Cyanobionts of Ornithocercus dinoflagellates Live cyanobionts (cyanobacterial symbionts) belonging to Ornithocercus dinoflagellate host consortium (a) O. magnificus with numerous cyanobionts present in the upper and lower girdle lists (black arrowheads) of the cingulum termed the symbiotic chamber. (b) O. steinii with numerous cyanobionts inhabiting the symbiotic chamber. (c) Enlargement of the area in (b) showing two cyanobionts that are being divided by binary transverse fission (white arrows). -
Epiphytic Calothrix cyanobacteria (arrows) in symbiosis with a Chaetoceros diatom. Scale bar 50 μm. -
Light microscope view of cyanobacteria from a microbial mat
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Cell death in eukaryotes and cyanobacteria Types of cell death according to the Nomenclature Committee on Cell Death (upper panel; and proposed for cyanobacteria (lower panel). Cells exposed to extreme injury die in an uncontrollable manner, reflecting the loss of structural integrity. This type of cell death is called "accidental cell death" (ACD). “Regulated cell death (RCD)” is encoded by a genetic pathway that can be modulated by genetic or pharmacologic interventions. Programmed cell death (PCD) is a type of RCD that occurs as a developmental program, and has not been addressed in cyanobacteria yet. RN, regulated necrosis. -
Synechococcus uses a gliding technique to move at 25 μm/s. Scale bar is about 10 µm.
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Cyanobacteria cultured in specific media: Cyanobacteria can be helpful in agriculture as they have the ability to fix atmospheric nitrogen in soil.
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Spirulina tablets
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Cyanobacteria activity turns Coatepeque Caldera lake a turquoise color
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Cyanobacterial bloom near Fiji
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Cyanobacteria in Lake Köyliö.
See also
In Spanish: Cyanobacteria para niños
