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Opisthokont Fossil range: Neoproterozoic - Recent
Scientific classification
Domain: Eukaryota (unranked) Opisthokonta

The opisthokonts (Greek: οπίσθω- (opisthō-) = "rear, posterior" + κοντός (kontos) = "pole" i.e. flagellum) are a broad group of eukaryotes, including both the animal and fungus kingdoms, together with the phylum Choanozoa and Mesomycetozoa of the protist "kingdom". Both genetic and ultrastructural studies strongly support that opisthokonts form a monophyletic group. One common characteristic is that flagellate cells, such as most animal sperm and chytrid spores, propel themselves with a single posterior flagellum. This gives the groups its name. In contrast, flagellate cells in other eukaryote groups propel themselves with one or more anterior flagella. Image File history File links Unbalanced_scales. ... Image File history File links This is a lossless scalable vector image. ... The Neoproterozoic Era is the unit of geologic time from 1,000 to 542 +/- 0. ... Operation Autumn Clouds: Israel Defense Forces troops kill two Palestinian terrorists in anorthern Gaza Strip operation. ... ImageMetadata File history File links Download high resolution version (1600x1200, 641 KB) Summary Author: User:PrzemekL. The picture is taken in Beskid Sadecki, Poland. ... For other uses, see Scientific classification (disambiguation). ... Kingdoms Animalia - Animals Fungi Plantae - Plants Chromalveolata Protista Alternative phylogeny Unikonta Opisthokonta Metazoa Choanozoa Eumycota Amoebozoa Bikonta Apusozoa Cabozoa Rhizaria Excavata Corticata Archaeplastida Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms whose cells are organized into complex structures by internal membranes and a cytoskeleton. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Chromalveolata Protista Alternative phylogeny Unikonta Opisthokonta Metazoa Choanozoa Eumycota Amoebozoa Bikonta Apusozoa Cabozoa Rhizaria Excavata Corticata Archaeplastida Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms whose cells are organized into complex structures by internal membranes and a cytoskeleton. ... For other uses, see Animal (disambiguation). ... For the fictional character, see Fungus the Bogeyman. ... In biological taxonomy, a kingdom or regnum is a taxon in either (historically) the highest rank, or (in the new three-domain system) the rank below domain. ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Classes Choanoflagellatea Corallochytrids Mesomycetozoea Nucleariids Choanozoa (Greek: (choanos) = funnel + (zōon) = animal) is the name of a phylum of protists that belongs to the line of opisthokonts. ... Typical phyla Chromalveolata Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) Cabozoa Excavata Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Archaeplastida (in part) Rhodophyta (red algae) Glaucophyta (basal archaeplastids) Amoebozoa Choanozoa Many others; classification varies Protists (IPA: (RP); (GenAm)), Greek protiston -a meaning the (most) first of all... This article is about the general scientific term. ... In phylogenetics, a group is monophyletic (Greek: of one stem) if all organisms in that group are known to have developed from a common ancestral form, and all descendants of that form are included in the group. ... Flagellata from Ernst Haeckels Artforms of Nature, 1904 Parasitic excavate (Giardia lamblia) Green alga (Chlamydomonas) Flagellates are cells with one or more whip-like organelles called flagella. ... A spermatozoon or spermatozoan ( spermatozoa), from the ancient Greek σπέρμα (seed) and (living being) and more commonly known as a sperm cell, is the haploid cell that is the male gamete. ... Orders Chytridiales Spizellomycetales Blastocladiales Monoblepharidales Neocallimasticales Chytridiomycota is a division of the Fungi kingdom and contains only one class, Chytridiomycetes. ...

The close relationship between animals and fungi was suggested by Cavalier-Smith in 1987, who used the informal name opisthokonta (the formal name has been used for the chytrids), and was confirmed by later genetic studies. Early phylogenies placed them near the plants and other groups that have mitochondria with flat cristae, but this character varies. Cavalier-Smith and Stechmann argue that the uniciliate eukaryotes such as opisthokonts and Amoebozoa, collectively called unikonts, split off from the other biciliate eukaryotes, called bikonts, shortly after they evolved. Thomas Cavalier-Smith is a professor of evolutionary biology at the University of Oxford, and is winner of the International Prize for Biology 2004 and one of the most notable researchers concerning the relationships, development, and classification of living things. ... For other uses, see Plant (disambiguation). ... Electron micrograph of a mitochondrion showing its mitochondrial matrix and membranes In cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed organelle that is found in most eukaryotic cells. ... Subgroups Mycetozoa(slime moulds) Archamoebae    Pelobiontida    Entamoebida Gymnamoebia Various others The Amoebozoa are a major group of amoeboid protozoa, including the majority that move by means of internal cytoplasmic flow. ... Supergroups Opisthokonta Amoebozoa Unikont is a eukaryotic cell with a single flagellum, at least ancestrally. ... A Bikont is a eukaryotic cell with two flagella. ... This article is about evolution in biology. ...

See also

References

• Cavalier-Smith, T. (1987). "The origin of fungi and pseudofungi", in Rayner, Alan D. M. (ed.): Evolutionary biology of Fungi. Cambridge: Cambridge Univ. Press, 339-353. ISBN 0-521-33050-5. 
• Wainwright, P.O.; et al. (1993). "Monophyletic origins of the metazoa: an evolutionary link with fungi". Science 260: 340-342. ISSN 0036-8075.
• Stechmann, A.; Cavalier-Smith, T. (2002). "Rooting the eukaryote tree by using a derived gene fusion". Science 297: 89–91. ISSN 0036-8075.