|
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] |
Ciliate
The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to flagellum, eukaryotic flagella, but are in general shorter and present in much larger numbers, with a different wikt:undulating, undulating pattern than flagella. Cilia occur in all members of the group (although the peculiar Suctoria only have them for part of their biological life cycle, 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 Ectosymbiosis, ectosymbiotic and endosymbiotic species, as well as some Obligate parasite, obligate and Facultative parasite, opportunistic parasites. Ciliate species r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stichotrich
The stichotrichs were a proposed group of ciliates, in the class Spirotrich, Spirotrichea. In a classification system proposed by Eugene Small and Denis Lynn in 1985, Stichotrichia formed a subclass containing four orders: Stichotrichida, Urostylida, Sporadotrichida and Plagiotomida. Although the group was made up of species traditionally classified among the "Hypotrich, hypotrichs"--ciliates possessing compound Cilium, ciliary Organelle, organelles called Cirrus (biology), cirri--it excluded euplotid ciliates such as ''Euplotes'' and ''Diophrys'', which were placed in the subclass Hypotrichia. In later classifications proposed by Denis Lynn, Stichotrichia omits the order Plagiotomida (species in that group were relocated to the order Stichotrichida). In more recent classifications, members of Stichotrichia, as defined by Small and Lynn., are placed in the subclass Hypotrich, Hypotrichia, and euplotid ciliates are placed in the subclass Euplotia. Like the euplotids, stichotric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holotrich
Holotricha is an order of ciliates. The classification has fallen from use as a formal taxon, but the terms "holotrich" and "holotrichous" are still applied descriptively to organisms with cilia of uniform length distributed evenly over the surface of the body. Etymology The term ''holotrich'' derives from the ancient greek (), meaning "whole, entire", and , (), meaning 'hair', because of the even distribution of cilia over the surface of the cell. Classification The order Holotricha was erected in 1859 by Friedrich Stein, who developed a system of classification in which ciliates were categorized according to the type and distribution of their cilia. The four major subdivisions of Stein's Ciliata were: Heterotricha, Peritricha, Hypotricha and Holotricha. The latter was reserved for organisms with cilia covering the entire surface of the body. The order included five families, within which a very diverse collection of genera were grouped. Among the better-known ciliates in Stein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciliate MDS/IES Database
In bioinformatics, the Ciliate MDS/IES database is a biological database of spirotrich genes. See also * 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 ... References External links * http://oxytricha.princeton.edu/dimorphism/database.htm. Biological databases Spirotrichea {{Biodatabase-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choreotrich
The choreotrichs are a group of small marine 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 differen ...s. Their name reflects the impression that they appear to dance ('choreo' as in choreography). The group includes the tintinnids, which produce species-specific loricae (shells), and are important because these may be preserved as microfossils. The cyst forms have been suggested to be affiliated to Chitinozoans, although other studies suggest Chitinozoans to have affinities to larger marine animals, and not tintinnids. Often they have been included among the oligotrichs. Tintinnids seem to be an excessively specious group as over 400 living species have been described, based on characteristics of the lorica or shell. Choreotrichs (including tintinnids) are part of the micro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypotrichia
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] |
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] |
Choreotrich
The choreotrichs are a group of small marine 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 differen ...s. Their name reflects the impression that they appear to dance ('choreo' as in choreography). The group includes the tintinnids, which produce species-specific loricae (shells), and are important because these may be preserved as microfossils. The cyst forms have been suggested to be affiliated to Chitinozoans, although other studies suggest Chitinozoans to have affinities to larger marine animals, and not tintinnids. Often they have been included among the oligotrichs. Tintinnids seem to be an excessively specious group as over 400 living species have been described, based on characteristics of the lorica or shell. Choreotrichs (including tintinnids) are part of the micro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligotrich
The oligotrichs are a group of ciliates, included among the spirotrichs. They have prominent oral cilia, which are arranged as a collar and lapel, in contrast to the choreotrichs where they form a complete circle. The body cilia are reduced to a girdle and ventral cilia. In ''Halteria'' and its relatives, they form bristles or cirri; however these forms may be closer relatives of the stichotrichs than of other oligotrichs. These organisms are very common in plankton communities, especially in marine systems. Usually found in concentrations of about 1 per ml, they are the most important herbivores in the sea, the first link in the food chain A food chain is a linear network of links in a food web starting from producer organisms (such as grass or algae which produce their own food via photosynthesis) and ending at an apex predator species (like grizzly bears or killer whales), de .... File:643 oligotrich-ciliate.jpg, Oligotrich ciliate, probably ''Strombidium'' File:Ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligotrich
The oligotrichs are a group of ciliates, included among the spirotrichs. They have prominent oral cilia, which are arranged as a collar and lapel, in contrast to the choreotrichs where they form a complete circle. The body cilia are reduced to a girdle and ventral cilia. In ''Halteria'' and its relatives, they form bristles or cirri; however these forms may be closer relatives of the stichotrichs than of other oligotrichs. These organisms are very common in plankton communities, especially in marine systems. Usually found in concentrations of about 1 per ml, they are the most important herbivores in the sea, the first link in the food chain A food chain is a linear network of links in a food web starting from producer organisms (such as grass or algae which produce their own food via photosynthesis) and ending at an apex predator species (like grizzly bears or killer whales), de .... File:643 oligotrich-ciliate.jpg, Oligotrich ciliate, probably ''Strombidium'' File:Ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tintinnid
Tintinnids are ciliates of the choreotrich order Tintinnida, distinguished by vase-shaped shells, the name deriving from a Latin source meaning a small tinkling bell, that are called'' loricae'', which are mostly protein but may incorporate minute pieces of minerals. Fossil record Fossils resembling tintinnid loricas in shape and size, Calpionellids, appear as early as the Ordovician period but are formed of calcite and as no extant ciliate taxa forms calcite shells they are unlikely to be tintinnids and probably not ciliates at all. Fossils which can be reliably related to extant tintinnids (e.g. fossils of agglutinated lorica) are in the fossil record during the Jurassic but do not become abundant until the Cretaceous. Tintinnids are an important part of the fossil record because of the rarity with which most other ciliates become preserved under the conditions of the marine environment. The loricae of some tintinnids are easily preserved, giving them a relatively good fossi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peritrich
The peritrichs (Latin: Peritrichia) are a large and distinctive group of ciliates. The peritrichs were first defined by Friedrich von Stein in 1859. Initially they were considered spirotrichs, then treated as a separate category, before receiving their modern placement. Structure They are usually bell or disc shaped, with a prominent paroral membrane arising from the oral cavity and circling counter-clockwise around the anterior of the cell, accompanied by a smaller series of membranelles. The oral cavity is apical and funnel shaped, with a contractile vacuole discharging directly into it. When disturbed, the anterior of the cell can contract. The rest of the body is unciliated, except for a ''telotroch band'' circling the posterior in mobile species and stages. Order Sessilida The larger order of Peritrichia are the Sessilida. Most of these have modified posterior kinetosomes which secrete a contractile stalk. The unattached stage, called a telotroch, is mouthless. These ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Stichotrich")
