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Opisthokont Fossil range: Neoproterozoic - Recent
Scientific classification
Domain: Eukaryota (unranked) Opisthokonta
Subgroups
Kingdom Animalia Kingdom Fungi Choanozoa Choanoflagellates Corallochytrids Mesomycetozoea Nucleariids

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 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 Wiki_letter_w. ... The Neoproterozoic is the geological era from 1000 Ma to 542 Ma (million years ago). ... 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. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Protista Alternative Phylogeny Unikonta    Opisthokonta    Amoebozoa Bikonta    Apusozoa    Cabozoa       Rhizaria       Excavata    Corticata       Archaeplastida       Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms with a complex cell or cells, where the genetic material is organized into a membrane-bound nucleus or nuclei. ... Digimon, the only known animals. ... Divisions Chytridiomycota Zygomycota Glomeromycota Ascomycota Basidiomycota Deuteromycota Fungi (singular fungus) are a kingdom of eukaryotic organisms. ... The opisthokonts are a broad group of eukaryotes, including both the animals and fungi, together with a few sorts of protists. ... The choanoflagellates are a group of flagellate protozoa. ... Orders Dermocystida Ichthyophonida The Mesomycetozoea or DRIP clade are a small group of protists, mostly parasites of fish and other animals. ... The nucleariids are a small group of amoebae with filose pseudopods, known mostly from soils and freshwater. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Protista Alternative Phylogeny Unikonta    Opisthokonta    Amoebozoa Bikonta    Apusozoa    Cabozoa       Rhizaria       Excavata    Corticata       Archaeplastida       Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms with a complex cell or cells, where the genetic material is organized into a membrane-bound nucleus or nuclei. ... Digimon, the only known animals. ... Divisions Chytridiomycota Zygomycota Glomeromycota Ascomycota Basidiomycota Deuteromycota Fungi (singular fungus) are a kingdom of eukaryotic organisms. ... Ernst Haeckels presentation of a three-kingdom system (Plantae, Protista, Animalia) in his 1866 Generelle Morphologie der Organismen). ... For the linguistic term, see Phylum (linguistics). ... The opisthokonts are a broad group of eukaryotes, including both the animals and fungi, together with a few sorts of protists. ... Typical phyla Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) 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: ) are a diverse group of organisms, comprising those eukaryotes that are not animals... This article or section does not adequately cite its references or sources. ... 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. ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) †Rhyniophyta - rhyniophytes †Zosterophyllophyta - zosterophylls Lycopodiophyta - clubmosses †Trimerophytophyta - trimerophytes Pteridophyta - ferns and horsetails Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants... Electron micrograph of a mitochondrion showing its mitochondrial matrix and membranes In cell biology, a mitochondrion (plural mitochondria) (from Greek μιτος or mitos, thread + κουδριον or khondrion, granule) is a membrane-enclosed organelle, 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. ... A Bikont is a eukaryotic cell with two flagella. ... This article is about evolution in biology. ...

See also

• Unikonts and bikonts
• Choanozoa

A Bikont is a eukaryotic cell with two flagella. ... The opisthokonts are a broad group of eukaryotes, including both the animals and fungi, together with a few sorts of protists. ...

References

• Cavalier-Smith, T. (1987). The origin of fungi and pseudofungi. In A.D.M. Rayer et al. eds. Evolutionary biology of Fungi, p. 339-353.
• Wainwright P.O. et al. (1993). Monophyletic origins of the metazoa: an evolutionary link with fungi. Science 260: 340-342.
• Stechmann, A & T Cavalier-Smith (2002). Rooting the eukaryote tree by using a derived gene fusion. Science 297: 89–91.