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Euplotes Charon
''Euplotes'' is a genus of ciliates in the subclass Euplotia. Species are widely distributed in marine and freshwater environments, as well as soil and moss. Most members of the genus are free-living, but two species have been recorded as commensal organisms in the digestive tracts of sea urchins. Description ''Euplotes'' cells are inflexible, dorsoventrally flattened, and roughly ovoid, with a very large oral region (peristome) bordered on the left by a long "adoral zone of membranelles" (AZM). Like other spirotrich ciliates, ''Euplotes'' move and feed with the help of compound ciliary organelles called "cirri," made up of thick tufts of cilia sparsely distributed on the cell. Strong cirri on the ventral surface of the cell enable ''Euplotes'' to walk or crawl on submerged detritus and vegetation. All species of ''Euplotes'' have a group of stiff bristles ( caudal cirri), which protrude from the posterior of the cell. The number of caudal cirri varies, even within a specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
Eukaryotes () are organisms whose Cell (biology), cells have a cell nucleus, nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the Three-domain system, three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard (archaea), Asgard archaea. This implies that there are only Two-domain system, two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass (ecology), biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as Flagellated cell, flagellated phagotrophs. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commensalism
Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit from each other; amensalism, where one is harmed while the other is unaffected; parasitism, where one is harmed and the other benefits, and parasitoidism, which is similar to parasitism but the parasitoid has a free-living state and instead of just harming its host, it eventually ends up killing it. The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected. The commensal relation is often between a larger host and a smaller commensal; the host organism is unmodified, whereas the commensal species may show great structural adaptation consistent with its habits, as in the remoras that ride attached to sharks and other fishes. Remo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypotrichea
The hypotrichs are a group of ciliated protozoa, common in fresh water, salt water, soil and moss. Hypotrichs possess compound ciliary organelles called "cirri," which are made up of thick tufts of cilia, sparsely distributed on the ventral surface of the cell. The multiple fused cilia which form a cirrus function together as a unit, enabling the organism to crawl along solid substrates such as submerged debris or sediments. Hypotrichs typically possess a large oral aperture, bordered on one side by a wreath or collar of membranelles (small membranous structures made up of fused cilia), forming an "adoral zone of membranelles," or AZM. Classification In older systems of classification, the term hypotrich comprised all ciliates possessing a relatively flattened body shape, strong cirri restricted to the ventral surface, and a large oral region (peristome) partially surrounded by an "adoral zone of membranelles". From a phylogenetic point of view, this historic grouping--whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euplotes Harpa - Alfred Kahl
''Euplotes'' is a genus of ciliates in the subclass Euplotia. Species are widely distributed in marine and freshwater environments, as well as soil and moss. Most members of the genus are free-living, but two species have been recorded as commensal organisms in the digestive tracts of sea urchins. Description ''Euplotes'' cells are inflexible, dorsoventrally flattened, and roughly ovoid, with a very large oral region (peristome) bordered on the left by a long "adoral zone of membranelles" (AZM). Like other spirotrich ciliates, ''Euplotes'' move and feed with the help of compound ciliary organelles called "cirri," made up of thick tufts of cilia sparsely distributed on the cell. Strong cirri on the ventral surface of the cell enable ''Euplotes'' to walk or crawl on submerged detritus and vegetation. All species of ''Euplotes'' have a group of stiff bristles ( caudal cirri), which protrude from the posterior of the cell. The number of caudal cirri varies, even within a specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypotrich
The hypotrichs are a group of ciliated protozoa, common in fresh water, salt water, soil and moss. Hypotrichs possess compound ciliary organelles called " cirri," which are made up of thick tufts of cilia, sparsely distributed on the ventral surface of the cell. The multiple fused cilia which form a cirrus function together as a unit, enabling the organism to crawl along solid substrates such as submerged debris or sediments. Hypotrichs typically possess a large oral aperture, bordered on one side by a wreath or collar of membranelles (small membranous structures made up of fused cilia), forming an "adoral zone of membranelles," or AZM. Classification In older systems of classification, the term hypotrich comprised all ciliates possessing a relatively flattened body shape, strong cirri restricted to the ventral surface, and a large oral region (peristome) partially surrounded by an "adoral zone of membranelles". From a phylogenetic point of view, this historic grouping--wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Friedrich Müller
Otto Friedrich Müller, also known as Otto Friedrich Mueller (2 November 1730 – 26 December 1784) was a Danish naturalist and scientific illustrator. Biography Müller was born in Copenhagen. He was educated for the church, became tutor to a young nobleman, and after several years' travel with him, settled in Copenhagen in 1767, and married a lady of wealth. His first important works, ''Fauna Insectorum Friedrichsdaliana'' (Leipzig, 1764), and ''Flora Friedrichsdaliana'' (Strasbourg, 1767), giving accounts of the insects and flora of the estate of Frederiksdal, near Copenhagen, recommended him to Frederick V of Denmark, by whom he was employed to continue the ''Flora Danica'' a comprehensive atlas of the flora of Denmark. Müller added two volumes to the three published by Georg Christian Oeder since 1761. The study of invertebrates began to occupy his attention almost exclusively, and in 1771 he produced a work in German on “Certain Worms inhabiting Fresh and Salt Water,†... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euplotes Patella From Ehrenberg
''Euplotes'' is a genus of ciliates in the subclass Euplotia. Species are widely distributed in marine and freshwater environments, as well as soil and moss. Most members of the genus are free-living, but two species have been recorded as commensal organisms in the digestive tracts of sea urchins. Description ''Euplotes'' cells are inflexible, dorsoventrally flattened, and roughly ovoid, with a very large oral region (peristome) bordered on the left by a long "adoral zone of membranelles" (AZM). Like other spirotrich ciliates, ''Euplotes'' move and feed with the help of compound ciliary organelles called "cirri," made up of thick tufts of cilia sparsely distributed on the cell. Strong cirri on the ventral surface of the cell enable ''Euplotes'' to walk or crawl on submerged detritus and vegetation. All species of ''Euplotes'' have a group of stiff bristles ( caudal cirri), which protrude from the posterior of the cell. The number of caudal cirri varies, even within a specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macronucleus
A macronucleus (formerly also meganucleus) is the larger type of nucleus in ciliates. Macronuclei are polyploid and undergo direct division without mitosis. It controls the non-reproductive cell functions, such as metabolism. During conjugation, the macronucleus disintegrates, and a new macronucleus is formed by karyogamy of the micronuclei. The macronucleus contains hundreds to thousands of chromosomes, each present in many copies. The macronucleus lacks a mechanism to precisely partition this complex genome equally during nuclear division; thus, how the cell manages to maintain a balanced genome after generations of divisions is unknown. See also *Micronucleus Micronucleus is the name given to the small nucleus that forms whenever a chromosome or a fragment of a chromosome is not incorporated into one of the daughter nuclei during cell division. It usually is a sign of genotoxic events and chromosomal i ... References . Cell nucleus Ciliate biology {{Ciliat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cilium
The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike projection that extends from the surface of the much larger cell body. Eukaryotic flagella found on sperm cells and many protozoans have a similar structure to motile cilia that enables swimming through liquids; they are longer than cilia and have a different undulating motion. There are two major classes of cilia: ''motile'' and ''non-motile'' cilia, each with a subtype, giving four types in all. A cell will typically have one primary cilium or many motile cilia. The structure of the cilium core called the axoneme determines the cilium class. Most motile cilia have a central pair of single microtubules surrounded by nine pairs of double microtubules called a 9+2 axoneme. Most non-motile cilia have a 9+0 axoneme that lacks the central pair o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organelle
In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as organs are to the body, hence ''organelle,'' the suffix ''-elle'' being a diminutive. Organelles are either separately enclosed within their own lipid bilayers (also called membrane-bound organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane bound organelles). Although most organelles are functional units within cells, some function units that extend outside of cells are often termed organelles, such as cilia, the flagellum and archaellum, and the trichocyst. Organelles are identified by microscopy, and can also be purified by cell fractionation. There are many types of organelles, particularly in eukaryotic cells. They include structures that make up the endomembrane system (such as the nuclear envelope, endoplasmic reticulum, and G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirotrich
The spirotrichs are a large and diverse group of ciliate protozoa. They typically have prominent oral cilia in the form of a series of polykinetids, called the adoral zone of membranelles, beginning anterior to the oral cavity and running down to the left side of the mouth. There may also be one or two paroral membranes on its right side. The body cilia are fused to form polykinetids called cirri in some, and are sparse to absent in others. Forms with cirri are common throughout soil, freshwater, and marine environments. Individuals tend to be flattened, with cirri confined to the ventral surface. These are variously used for crawling over objects, acting as feet, swimming, or assisting in food capture. They are generally divided into hypotrichs and stichotrichs, but were originally all considered hypotrichs. Forms with sparse or absent body cilia tend to be smaller and are mostly marine, but a few are common in freshwater. Again, they are generally divided into oligotrich ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membranelle
Membranelles (also membranellae) are structures found around the mouth, or cytostome, in ciliates. They are typically arranged in series, to form an "adoral zone of membranelles," or AZM, on the left side of the buccal cavity (peristome). The membranelles are made up of kinetosomes arranged in groups to make up ''polykinetids''. The cilia The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike proje ... which emerge from these structures appear to be fused and to function as a single membrane, which can be used to sweep particles of food into the cytostome, or for locomotion.Kudo, Richard R. Protozoology. 4th ed. Charles C. Thomas, 1954. p. 59. References Organelles Ciliate biology {{cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
