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Ciliate
The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general shorter and present in much larger numbers, with a different undulating pattern than flagella. Cilia occur in all members of the group (although the peculiar Suctoria only have them for part of their life cycle) and are variously used in swimming, crawling, attachment, feeding, and sensation. Ciliates are an important group of protists, common almost anywhere there is water—in lakes, ponds, oceans, rivers, and soils. About 4,500 unique free-living species have been described, and the potential number of extant species is estimated at 27,000–40,000. Included in this number are many ectosymbiotic and endosymbiotic species, as well as some obligate and opportunistic parasites. Ciliate species range in size from as little as 10 µm in some colpodeans to as much as 4 mm in length in some g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paramecium
'' ''Paramecium'' ( , ; also spelled ''Paramoecium'') is a genus of eukaryotic, unicellular ciliates, commonly studied as a representative of the ciliate group. ''Paramecia'' are widespread in freshwater, brackish, and marine environments and are often very abundant in stagnant basins and ponds. Because some species are readily cultivated and easily induced to conjugate and divide, it has been widely used in classrooms and laboratories to study biological processes. Its usefulness as a model organism has caused one ciliate researcher to characterize it as the " white rat" of the phylum Ciliophora. Historical background ''Paramecia'' were among the first ciliates to be seen by microscopists, in the late 17th century. They were probably known to the Dutch pioneer of protozoology, Antonie van Leeuwenhoek, and were clearly described by his contemporary Christiaan Huygens in a letter of 1678. The earliest known illustration of a Paramecium was published anonymously in Philosophi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karyorelictea
Karyorelictea is a class of ciliates in the subphylum Postciliodesmatophora. Most species are members of the microbenthos community, that is, microscopic organisms found in the marine interstitial habitat, though one genus, ''Loxodes'', is found in freshwater. The majority of karyorelict taxa have not been cultivated in the laboratory, although clonal lines of ''Loxodes'' have been developed. Systematics According to Lynn (2008), the Karyorelictea class is divided into three orders: * Loxodida, containing the families Cryptopharyngidae and Loxodidae; * Protoheterotrichida, containing the families Aveliidae and Geleiidae; * Protostomatida, containing the families Kentrophoridae and Trachelocercidae. These three orders were defined morphologically, and have been confirmed with molecular phylogenetics. An additional family, Wilbertomorphidae, is of uncertain affiliation and has not been assigned to an order. Nuclear dimorphism All ciliates, including karyorelicteans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coleps
''Coleps'' is a genus of ciliates in the class Prostomatea with barrel-shaped bodies surrounded by regularly arranged plates composed of calcium carbonate. Description Species of ''Coleps'' can grow up to 250 µm in length, but are usually under 100 µm in their longest axis. ''Coleps'' can be taxonomically distinguished by the ornamentation of the ectoplasmic plates which make up their test. These plates are located outside alveolar vesicles of the cell cortex, and contain both organic and inorganic components, the latter of which is mostly amorphous calcium carbonate. Predatory behavior ''Coleps'' feeds on bacteria, algae, flagellate A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word ''flagellate'' also describes a particular construction (or level of organization) characteristic of many prokaryotes and eukaryotes and thei ...s, living and dead ciliates, animal and plant tissues. ''Coleps'' uses toxic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alveolate
The alveolates (meaning "pitted like a honeycomb") are a group of protists, considered a major clade and superphylum within Eukarya. They are currently grouped with the stramenopiles and Rhizaria among the protists with tubulocristate mitochondria, the group being referred to as SAR. Characteristics The most notable shared characteristic is the presence of cortical (near the surface) alveoli (sacs). These are flattened vesicles (sacs) arranged as a layer just under the membrane and supporting it, typically contributing to a flexible pellicle (thin skin). In armored dinoflagellates they may contain stiff plates. Alveolates have mitochondria with tubular cristae (invaginations), and cells often have pore-like intrusions through the cell surface. The group contains free-living and parasitic organisms, predatory flagellates, and photosynthetic organisms. Almost all sequenced mitochondrial genomes of ciliates and apicomplexa are linear. The mitochondria almost all carry mtD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intramacronucleata
Intramacronucleata is a subphylum of ciliates. The group is characterized by the manner in which division of the macronucleus is accomplished during binary fission of the cell. In ciliates of this subphylum, division of the macronucleus is achieved by the action of microtubules which are assembled ''inside'' the macronucleus itself. This is in contrast to heterotrich The heterotrichs are a class of ciliates. They typically have a prominent adoral zone of membranelles circling the mouth, used in locomotion and feeding, and shorter cilia on the rest of the body. Many species are highly contractile, and are t ... ciliates of the subphylum Postciliodesmatophora, in which division of the macronucleus relies on microtubules formed ''outside'' the macronuclear envelope. References * * External links * Ciliate taxonomy Bikont subphyla {{Ciliate-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllopharyngea
The Phyllopharyngea are a class of ciliates, some of which are extremely specialized. Motile cells typically have cilia restricted to the ventral surface, or some part thereof, arising from monokinetids with a characteristic ultrastructure. In both chonotrichs and suctoria, however, only newly formed cells are motile and the sessile adults have undergone considerable modifications of form and appearance. Chonotrichs, found mainly on crustaceans, are vase-shaped, with cilia restricted to a funnel leading down into the mouth. Mature suctorians lack cilia altogether, and initially were not classified as ciliates. The mouths of Phyllopharyngea are characteristically surrounded by microtubular ribbons, called ''phyllae''. Nematodesmata, rods found in several other classes of ciliates, occur among the subclass Phyllopharyngia, most of which are free-living. In others, the mouth is often modified to form an extensible tentacle, with toxic extrusomes at the tip. These are espec ... [...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 oligotri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muranotrichea
Muranotrichea is a class of free-living marine anaerobic ciliates, that, together with the classes Parablepharismea and Armophorea, form a major clade of obligate anaerobes within the SAL group ( Spirotrichea, Armophorea, and Litostomatea). Muranotrichea are medium to large, elongated holotrichous ciliates with contractile body and somatic ciliature composed of dikinetids. Their oral ciliature includes an elongated key-hole shaped peristome, an adoral zone of membranelles spiraling rightward around distinctly neck-like anterior body part; and heteromorphic paroral membrane . They inhabit micro-oxic marine to brackish sediments and host prokaryotic ectosymbionts and endosymbionts. The class contains a single order Muranotrichida and family Muranotrichidae. Muranotrichidae include two species, ''Muranothrix'' ''gubernata'' and ''Thigmothrix strigosa''. Muranotrichea together with Parablepharismea Parablepharismea is a class of free-living marine and brackish anaerobic cil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parablepharismea
Parablepharismea is a class of free-living marine and brackish anaerobic ciliates that form a major clade of obligate anaerobes within the SAL group ( Spirotrichea, Armophorea, and Litostomatea), together with the classes Muranotrichea and Armophorea Armophorea is a class of ciliates in the subphylum Intramacronucleata. . It was first resolved in 2004 and comprises three orders: Metopida, Clevelandellida, and Armophorida. Previously members of this class were thought to be heterotrichs beca .... Parablepharismea are medium to large, elongated ciliates with navicular outline and holotrichous somatic ciliature composed of dikinetids without postciliodesmata. Their oral ciliature is composed of bipartite paroral membrane and adoral zone of membranelles. They host a thick coat of prokaryotic ectosymbionts and cytoplasmic endosymbionts. They are found in micro-oxic marine to brackish habitats. Parablepharismea may be related to the deep sea Cariacotrichea ciliates. This clas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armophorea
Armophorea is a class of ciliates in the subphylum Intramacronucleata. . It was first resolved in 2004 and comprises three orders: Metopida, Clevelandellida, and Armophorida. Previously members of this class were thought to be heterotrichs because of similarities in morphology, most notably a characteristic dense arrangement of cilia surrounding their oral structures. However, the development of genetic tools and subsequent incorporation of DNA sequence information has led to major revisions in the evolutionary relationships of many protists, including ciliates. Metopids, clevelandellids, and armophorids were grouped into this class based on similarities in their small subunit rRNA sequences, making them one of two so-called "riboclasses" of ciliates, however, recent analyses suggest that Armophorida may not be related to the other two orders. Etymology The name Armophorea is thought to be derived from the Latin word ''arma,'' meaning weapons, or ''armus'', meaning shoulder. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plagiopylid
The plagiopylids are a small order of ciliates, including a few forms common in anaerobic habitats. The body cilia are dense, and arise from monokinetids with an entirely unique ultrastructure; one or two rows of dikinetids run into the oral cavity, which takes the form of a groove, with a deep tube lined by oral cilia leading to the mouth. The order was introduced by Eugen Small and Denis Lynn in 1985, who treated it as a subclass of Oligohymenophorea. Since then they tend to be treated as an independent class, possibly affiliated with the Colpodea. Class Plagiopylea is divided into two clades: one contains members of the order Plagiopylida (like '' Plagiopyla frontata'' and '' Trimyema compressum'') and the second clade contains plagiopylean ciliate associated with denitrifying obligate endosymbiont An ''endosymbiont'' or ''endobiont'' is any organism that lives within the body or cells of another organism most often, though not always, in a mutualistic relationship. (The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protocruziea
Protocruziea is a class of ciliates in the subphylum Intramacronucleata Intramacronucleata is a subphylum of ciliates. The group is characterized by the manner in which division of the macronucleus is accomplished during binary fission of the cell. In ciliates of this subphylum, division of the macronucleus is achi .... References * Intramacronucleata Monotypic SAR supergroup taxa Ciliate classes {{Ciliate-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
