Hawkins danced the challenging title role, the penitent who flagellates himself to attain fuller belief and enlightenment.
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A Shiite Muslim man flagellates with others during the religious procession ahead of Ashura in Lahore, Pakistan, on Sept. 9.
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Flagellates are the smallest members of the protozoa group, and can be divided further based on whether they can participate in photosynthesis. Nonchlorophyll- containing flagellates are not capable of photosynthesis because chlorophyll is the green pigment that absorbs sunlight. These flagellates are found mostly in soil. Flagellates that contain chlorophyll typically occur in aquatic conditions.
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In 1841, Gabriel Valentin found flagellates that today are included in Trypanoplasma in the blood of trout.Leadbeater, B.S.C & McCready, S.M.M. (2000). The Flagellates. Unity, diversity and evolution.
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Other flagellates were able to multiply at much lower bacterial concentrations, indicating that bacterial concentration is a limiting factor for Cafeteria. Flagellates have varying abilities to gather bacteria to their mouths with their flagella, and this study suggests that the abilities of Cafeteria species may be inferior to other flagellates, since Cafeteria are usually specific to niches with high concentrations of bacteria.
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Cercomonads are small flagellates, widespread in aqueous habitats and common in soils.
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Other notable filose cercozoans include the cercomonads, which are common soil flagellates.
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Cryptomonas has the meaning of hidden small flagellates from “crypto” and “monas”.
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The newly discovered protozoa were closely related to termites' intestinal flagellates. The existence of such flagellates had been known for many years, but it was Cleveland who discovered the symbiosis between the intestinal flagellates and their termite hosts and published the empirical proof in a series of papers from 1923 to 1928. He also established that the roach Cryptocercus depends upon symbiosis with its intestinal flagellates to utilize cellulose as food. From the early 1930s onward, most of his research was on taxonomic and experimental studies of the intestinal protozoa of Cryptocercus.
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Mastigamoeba are characterized as amoeboid flagellates with hyaline cytoplasm. The hyaline cytoplasm is clear. Mastigamoeba are polymorphic; they switch between multiple morphologies throughout their life cycles. They can exist as amoeboid flagellates, aflagellate amoebae, multinucleate amoebae, and as cysts.
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Cavalier-Smith, T. (1991). Cell diversification in heterotrophic flagellates. The Biology of Free-living Heterotrophic Flagellates. 113-131. The divisions between gonocytes are described as consisting of outer continuous membranes and flattened vesicles but pressed so closely together they are impossible to distinguish.
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Anoecida is an order of bicosoecids, a small group of unicellular flagellates, included among the heterokonts.
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Pseudodendromonadida is a subclass of bicosoecids, a small group of unicellular flagellates, included among the heterokonts.
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Nanum is a genus of bicosoecids, a small group of unicellular flagellates, included among the heterokonts.
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Borokiae is a superorder of bicosoecids, a small group of unicellular flagellates, included among the heterokonts.
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Cyathobodoniae is a subclass of bicosoecids, a small group of unicellular flagellates, included among the heterokonts.
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Bicosidia is a subclass of Bikosea, a small group of unicellular flagellates, included among the heterokonts.
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Rictus is a genus of Bikosea, a small group of unicellular flagellates, included among the heterokonts.
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Like termites, these cockroaches have symbiotic flagellates and bacteria in their gut that aid in digestion.
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Nucleophaga is a genus of eukaryotic microorganisms that are internal parasites of amoeba, flagellates, and ciliates.
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In marine pelagic environments, heterotrophic nano-flagellates are the most probable consumers of bacterial cell production. Cultured flagellates in laboratory experiments demonstrate that they are adapted to predation on bacteria-sized particles and occur in concentrations to control bacterial biomass. Tight fluctuations in numbers of bacteria and flagellates have been found in a eutrophic estuary, particularly in the summer. The amplitude of these fluctuations increases in response to artificial eutrophication with inorganic nutrients and decreases in response to predation.
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It is easy to understand the relation of the saprophytic and the holophytic Flagellates to true plants.
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Flagellate megaevolution: the basis for eukaryote diversification. In: Leadbeater, B.S.C., Green, J.C. (eds.). The Flagellates. Unity, diversity and evolution.
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Picoplankton also play an important role in the microbial loop of these systems by aiding in providing energy to higher trophic levels. They are grazed by a various number of organisms such as flagellates, ciliates, rotifers and copepods. Flagellates are their main predator due to their ability to swim towards picoplankton in order to consume them.
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Their functions range from bacterial photosynthesis (bacteriorhodopsin) to driving phototaxis (channelrhodopsins in flagellates). Signal transduction in phototaxis involves depolarization of the cell membrane.
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Ultrastructural characters are not known.David J. Patterson, Naja Vors, Alastair G.B. Simpson, Charles O. Kelly: Residual Free-Living And Predatory Heterotrophic Flagellates In: Residual Free-Living And Predatory Heterotrophic Flagellates In: Illustrated Guide to the Protozoa, 2nd Edition. Vol. 2, Society of Protozoologists, Lawrence, Kansas 2000, , p. 1302-1328. Kamera lens lives as a saprobiont and can be found in hay infusions.
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Several endoparasites have been found in gerrids. Trypanosamatid flagellates, nematodes, and parasitic Hymenoptera all act as endoparasites. Water mite larvae act as ectoparasites of water striders.
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They will appear to be small, translucent flagellates as individuals or in clusters. The undulating membrane may appear to exhibit wave-like motions when higher magnification is used.
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The flagellates break lignocellulose (xylan or cellulose) down into simple sugars, which they ferment for their own energy needs, producing CO2, H2, and short-chain fatty acids such as acetate as waste products. The short-chain fatty acids (which are also produced by homoacetogenic gut bacteria from CO2 and H2) can be directly absorbed by the termite host. The vast majority of digestion takes place in the paunch: almost all xylanase activity, just over one quarter of the endoglucanase activity, and almost two thirds of the exoglucanase activity in the R. flavipes digestive system is localised in the hindgut and attributed to gut flagellates. Although this is an obligate symbiosis, newly hatched larvae do not have gut flagellates.
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Flagellates can be distinguished by their flagella, which is their means of movement. Some have several flagella, while other species only have one that resembles a long branch or appendage.
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From 1925 to 1928 Kirby was an instructor in biology at Yale University. At U. C. Berkeley's zoology department, he was from 1928 to 1931 an assistant professor, from 1931 to 1940 an associated professor, and from 1940 until this death a full professor. Kirby devoted most of his career to the study of protists, specifically those flagellates that live in termite digestive tracts. He worked out a well-documented explanation of the evolutionary history of such flagellates.
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Bicosoecida (ICZN) or Bicosoecales/Bicoecea (ICBN) is an order of Bikosea, a small group of unicellular flagellates, included among the heterokonts. Informally known as bicosoecids, they are a small group of unicellular flagellates, included among the heterokonts. The cells are free-living, with no chloroplasts, and in some genera are encased in a lorica. The name of the type genus Bicosoeca described by James-Clark in 1866 is derived from Greek roots (, vase, bowl, plus oekein, inhabit).
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0.63081-0Although they are one of the most common flagellates found in freshwater, they are also able to tolerate saltwaterMorgan-Smith, D., Garrison, C. E., and Bochdansky, A. B. 2013: Mortality and survival of cultured surface-ocean flagellates under simulated deep-sea conditions. Journal of Experimental Marine Biology and Ecology, 445: 13-20. DOI: 10.1016/j.jembe.2013.03.017 Their ability to alternate between both marine and freshwater environments in many parts of the world give them a “cosmopolitan” character.
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Neobodo are free-living and active microbial predators that swim around and feed on prey in aquatic ecosystems. As free-living flagellates, they are the most important bacterivorous forms in aquatic environments. Neobodo, like other bodonids, are heterotrophic flagellates (HF) which are a very diverse and heterogeneous group of protists with a size range between 1 and 450 microns. They play an essential role in aquatic and terrestrial food webs as major consumers of bacterial biomass.
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Some old classifications included Opalinidae in the ciliates. The fundamental difference between multiciliate flagellates (e.g., hemimastigids, Stephanopogon, Multicilia, opalines) and ciliates is the presence of macronuclei in ciliates alone.Cavalier-Smith, T. (2000).
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Monocercomonoides species are obligate animal symbionts that live in the digestive tracts of insects, amphibians, reptiles, and mammals.Lauter, F. H. 1959. Haemoflagellates and intestinal flagellates from anura of Louisiana. Louisiana State University.
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The fungus left Bacteria of the genera Chromobacterium, Janthinobacterium, and Pseudoalteromonas produce a toxic secondary metabolite, violacein, to deter protozoan predation. Violacein is released when bacteria are consumed, killing the protozoan. Another bacteria, Pseudomonas aeruginosa, aggregates into quorum sensing biofilms which may aid the coordinated release of toxins to protect against predation by protozoans. Flagellates were allowed to grow and were present in a biofilm of P. aeruginosa grown for three days, but no flagellates were detected after seven days.
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This work formed his PhD thesis, titled "The cultivation of some intestinal flagellates of termites and the nature of the symbiosis between these protozoa and their insect host" which he was granted in 1933.
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Endocytobiology II: intracellular space as oligogenetic. Berlin: Walter de Gruyter & Co. pp. 1027–1034 Historically, amoeboid flagellates have been considered Pelobionts, which encompasses mastigamoebids and pelomyxids. There is contention with the naming of the genus.
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These include uncultured members of Endomicrobia (Elusimicrobia) and other taxa that live as cytoplasmic symbionts, as well as epibiotic symbionts that attach to the outer surface of cells. In R. flavipes, cytoplasmic symbionts have been identified in flagellates such as Trichonympha agilis (Hypermastigida) and Pyrsonympha vertens (Oxymonadida). The latter is also characterised by spirochaete epibiotic symbionts. In other termite species, members of the spirochaete genus Treponema have been identified as endo- and ectosymbionts of flagellates: similar associations may explain Treponema's dominance in the R. flavipes gut.
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These are acquired when the larvae are fed with flagellate-containing anal fluids from other members of the colony (proctodeal trophallaxis). Proctodeal trophallaxis is also used to replenish flagellates and other gut symbionts after each moult.
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It can also regenerate a new head within minutes, if the original is cut off. Lacrymaria feed primarily on smaller organisms such as other ciliates, flagellates, and amoeba, but may sometimes tear chunks out of larger ciliates.
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Australian physicians Fowler and Carter first described human disease caused by amebo-flagellates in Adelaide in 1965. Their work on amebo-flagellates has provided an example of how a protozoan can effectively live both freely in the environment, and in a human host. Since 1965, more than 144 cases have been confirmed in different countries. In 1966, Fowler termed the infection resulting from N. fowleri primary amoebic meningoencephalitis (PAM) to distinguish this central nervous system (CNS) invasion from other secondary invasions made by other amoebae such as Entamoeba histolytica.
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Bodonid flagellates (class Kinetoplastea) are abundant, free-living bacterivores that occur in a wide variety of environments including freshwater, soil and marine habitats ranging from the tropics to the Arctic. Neobodo is one of the most common flagellates in freshwater environments, but can also tolerate marine environments with low salinities of 3-4 ppt. Strains of Neobodo species isolated from different environments fall exclusively into marine and freshwater lineages. Studies show that Neobodo is a complex and ancient species with a major marine clade nested among older freshwater clades.
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Monocercomonoides is a genus of flagellate Excavata belonging to the order Oxymonadida. It was established by Bernard V. Travis and was first described as those with "polymastiginid flagellates having three anterior flagella and a trailing one originating at a single basal granule located in front of the anteriorly positioned nucleus, and a more or less well-defined axostyle".Travis, B. V. 1932. A Discussion of Synonymy in the Nomenclature of Certain Insect Flagellates, with the Description of a New Flagellate from the Larvae of Ligyrodes relictus Say (Coleoptera-Scarabaeidae).
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Over the course of her career, Radek has published almost 100 scientific papers, eleven book chapters, and two protistology textbooks. One of these textbooks, Protistology, has been translated into Chinese, Russian, and Korean. In 1991, she created a scientific film about termite flagellates with Klaus Hausmann. Her current focus is on the biology and morphology of protists that live as symbionts and parasites in diverse insect hosts, notably termite gut flagellates and spore-forming protists (some of which, like the nephridiophagids, are now thought to be fungi) in cockroaches and beetles.
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The euglyphids are traditionally grouped with other amoebae. However, genetic studies instead place them with various amoeboid and flagellate groups, forming an assemblage called the Cercozoa. Their closest relatives are the thaumatomonads, flagellates that form similar siliceous tests.
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M. membranacea can eat food particles such as bacteria, flagellates, diatoms, and other small, planktonic organisms by extracting them from the water with their lophophore. They can also supplement their diet with dissolved organic nutrients through the absorptive epidermis.
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Revue d'histoire des sciences, 27–44. The first groups used to classify microscopic organism were the Animalcules and the Infusoria.The Flagellates. Unity, diversity and evolution. Ed.: Barry S. C. Leadbeater and J. C. Green Taylor and Francis, London 2000, p. 3.
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Algae and Fungi McGraw-Hill Book Company Inc all unicellular flagellates, found in stagnant water and on damp soil, in freshwater, seawater, and even in snow as "snow algae".Hoham, R.W., Bonome, T.A., Martin, C.W. and Leebens-mack, J.H. 2002.
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Flagellates are a feature of all termite families except Termitidae, the so-called "higher termites". They are found exclusively in the hindgut, especially the paunch, an enlarged section of the hindgut with an anaerobic interior that serves as a fermenter. In R. flavipes, wood eaten by the termite is first broken up with the mandibles, treated with host endoglucanases from the salivary glands, ground up into small particles in the gizzard, and then treated with additional host cellulases in the midgut, freeing glucose for immediate absorption. It then passes into the paunch, where flagellates take up the partly-digested wood particles through endocytosis.
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Arificial defaunation of Reticulitermes species by force- feeding on starch or starvation leads to a loss of flagellates and, by association, these endosymbiotic Endomicrobia, and an increase in abundance of free-living relatives. A rare free-living member of this class, Endomicrobium proavitum, the first Endomicrobia species to be cultured and named, was isolated from sterile-filtered gut homogenates from defaunated (starch-fed) R. flavipes workers. It is believed to play a role in nitrogen fixation. While some gut bacteria live free in the gut lumen or attached to the gut wall, many others live in close association with flagellates.
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Stygiella /ˌstɪ.d͡ʒiˈɛ.lə/ is a genus of free-living marine flagellates belonging to the family Stygiellidae in the jakobids (excavata). The genus currently includes four species, all of which are secondary obligate anaerobes.. The species are all unicellular and crescent-shapedBernard, C, Simpson, A. G. B. & Patterson, D. J. (2000) Some free-living flagellates (protista) from anoxic habitats, Ophelia, 52:2, 113-142, DOI: 10.1080/00785236.1999.10409422.. All members possess hydrogenosomes, a type of acristate mitochondrion-derived organelle (MRO) that produces hydrogen gas as a metabolic productLeger, M. M., Eme, L., Hug, L. A., & Roger, A. J. (2016).
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Likewise, most fungi do not produce cells with flagellae, but the primitive fungal chytrids do. Many protists take the form of single-celled flagellates. Flagella are generally used for propulsion. They may also be used to create a current that brings in food.
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With the help of its ciliature, C. inflata alternates between gliding rather clumsily and resting in one spot, circling jerkily. C. inflata feeds almost exclusively on bacteria, in rare cases on flagellates. Digestion takes place within its 4-8 μm-sized food vacuoles.
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Ultrastructure of Trimastix pyriformis (Klebs) Bernard et al.: similarities of Trimastix species with retortamonad and jakobid flagellates. Protist, 150(2), 149-162. Trimastix species do not have mitochondria, but they do have remnants of an ancestral mitochondria, in the form of a mitosome.
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Most excavates are unicellular, heterotrophic flagellates. Only the Euglenozoa are photosynthetic. In some (particularly anaerobic intestinal parasites), the mitochondria have been greatly reduced. Some excavates lack "classical" mitochondria, and are called "amitochondriate", although most retain a mitochondrial organelle in greatly modified form (e.g.
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Protozoa are eukaryotic organisms that were some of the first microorganisms to reproduce sexually, a significant evolutionary step from duplication of spores, like those that many other soil microorganisms depend on. Protozoa can be split up into three categories: flagellates, amoebae and ciliates.
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Ciliates are the largest of the protozoa group, and move by means of short, numerous cilia that produce beating movements. Cilia resemble small, short hairs. They can move in different directions to move the organism, giving it more mobility than flagellates or amoebae.
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The katablepharids, a group of heterotrophic flagellates, have been considered as part of the Cryptista since katablepharids were described in 1939. Although they differ from other cryptophytes and have even been proposed to be alveolates, early 21st century research suggests they are related to cryptophytes.
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Petalomonas is a genus of phagotrophic, flagellated euglenoids.Guiry, M. D.; Guiry, G. M. (2002). “Petalomonas F.Stein 1859”. Retrieved February 10, 2019, from Phagotrophic euglenoids are one of the most important forms of flagellates in benthic aquatic systems, playing an important role in microbial food webs.
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The Oxymonads are a group of flagellated protozoa found exclusively in the intestines of termites and other wood-eating insects. Along with the similar parabasalid flagellates, they harbor the symbiotic bacteria that are responsible for breaking down cellulose. It includes Dinenympha, Pyrsonympha, and Oxymonas.
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Monocercomonoides are small free-swimming, single-cell organisms ranging from 5-12μm in length, and 4.5-14.5μm in width. The body may be ovoidal, pyriform, spherical or subspherical; however, they lack holdfasts and have small axostyles.Laird, M. 1955. Intestinal Flagellates from Some New Zealand Insects.
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Flagella are supported by microtubules in a characteristic arrangement, with nine fused pairs surrounding two central singlets. These arise from a basal body. In some flagellates, flagella direct food into a cytostome or mouth, where food is ingested. Flagella often support hairs, called mastigonemes, or contain rods.
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The sperm are highly motile, small and simple, but have no flagellates. The female antrum shows a simple anatomy and is only involved in laying eggs. Sperm of Macrostomum hystrix The needle-like stylet of Macrostomum hystrix. The seminal vesicle is visible, as are the developing eggs.
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Arcella inhabit freshwater pools, eutrophic waters, marshes, mosses, as well as wet foliage. Few species can also be found in soils. They nourish on diatoms, unicellular green algae or animal protozoa such as flagellates and ciliates. Most species are worldwide-distributed, but some have restricted distributions, e.g.
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Common genera in soil are Aspergillus, Mucor, Penicillium Trichoderma, Alternaria, Rhizopus. Algae – found in most of the soils in number ranges from 100 to 10,000 per g. Protozoa: Unicellular – population ranges from 10,000 to 100,000 per g of soil. Most of the soil forms are flagellates, amoebae or ciliates.
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A wide range of protozoans live commensally in the rumens of ruminant animals, such as cattle and sheep. These include flagellates, such as Trichomonas, and ciliated protozoa, such as Isotricha and Entodinium. The ciliate subclass Astomatia is composed entirely of mouthless symbionts adapted for life in the guts of annelid worms.
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These bacteria drive the food web of humic lakes by providing energy and supplying usable forms of organic and inorganic carbon to other organisms, primarily to phagotrophic and mixotrophic flagellates. Salonen, K, and Jokinen, S. 1988. Flagellate grazing on bacteria in a small dystrophic lake. Hydrobiologia, 161(1), 203-209.
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Grazing in the heterotrophic dinoflagellate Oxyrrhis marina: size selectivity and preference for calcified Emiliania huxleyi cells. Aquatic Microbial Ecology 10 307-13. It has been observed eating Nannochloris oculata and Micromonas pusilla, other flagellates such as Goniomonas amphinema, Pfiesteria piscicida, and Stoeckeria algicida, and some bacteria.Roberts, E. C., et al. (2011).
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A number of parabasalids and oxymonads are found in termite guts, and play an important role in breaking down the cellulose found in wood. Some other metamonads are parasites. These flagellates are unusual in lacking mitochondria. Originally they were considered among the most primitive eukaryotes, diverging from the others before mitochondria appeared.
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The species affects the composition of the phytoplankton community by decreasing the biomass of mostly toxic cyanobacteria and flagellates and promoting the biomass of mostly colonial green algae. Nitrogen concentrations may also be decreased. Its pronounced effect on water chemistry and community composition makes S. aeruginosa a keystone species in its habitat.
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Sometimes, young trophocytes possess an anterior beak, although its function is unknown. The trophont stage is a multicellular growth stage, composed of many individual cells wrapped by a cellulosic layer. Dinospores are free-swimming flagellates that exhibit the typical morphology of dinoflagellates. Although initially binucleated, they later divide into four uni-nucleated dinospores.
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For example, over-lapping caste system, age-depended polytheism. Moreover, this subfamily gut composed with bacterial community, rather than flagellates. These fungus growers might be encoded with natural antibiotics because colony does not shows infections so far. There are 14 genera which extended to 350 plus species so far in the subfamily.
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Binary fission in organisms can occur in four ways, irregular, longitudinal, transverse, oblique.i.e.left oblique & right oblique # Irregular: In this fission, cytokinesis may take place along any plane but it is always perpendicular to the plane of karyokinesis. e.g. amoeba # Longitudinal: Here cytokinesis takes place along the longitudinal axis. e.g. in flagellates like Euglena.
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The first person to observe and formally describe symbiotic flagellates in R. flavipes was the American paleontologist Joseph Leidy. In 1877, he reported his findings to the Academy of Natural Sciences of Philadelphia, describing three new species which he mistakenly took to be parasitic ciliates: Trichonympha agilis, Pyrsonympha vertens, and Dinenympha gracilis.
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They are most often found on marsh plants such as Sphagnum. This group was previously classified as the Gromiida or Gromiina. However, molecular studies separate Gromia from the others, which must therefore be renamed. They are placed among the Cercozoa, and presumably developed from flagellates like Cryothecomonas, which has a similar test.
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This suggests that surface-adapted flagellates can not only survive under deep-sea conditions but are able to reproduce and potentially provide seed populations in cold, high-pressure environments. Although Neobodo are not abundant in the deep oceans, they are capable of surviving in the deep waters, tolerating high pressure and low temperature conditions.
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Aided by this new technology, the scientists were able to declare variations in the path of the apical groove of the organism (found on the flagellar apparatus). Since the apical groove varies among species, the scientists used it to indicate differences between the unarmored flagellates. Akashiwo was one of four new genera that was redefined using the analysis.
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Kamera lens is a free-living, swimming, heterotrophic organism. It is 6 to 7 by 2.5 to 3 micrometers on averageH. M. Woodcock: Observations on Coprozoic Flagellates: Together with a Suggestion as to the Significance of the Kinetonucleus in the Binucleata, In: Philosophical Transactions of the Royal Society of London. Series B, Vol. 207, 1916, p.
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Prey such as bacteria and smaller flagellates is ingested through a cytostome, supported by microtubules. These are often packed together to form two or more rods, which function in ingestion, and in Entosiphon form an extendable siphon. Most phagotrophic euglenids have two flagella, one leading and one trailing. The latter is used for gliding along the substrate.
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The new genus Neobodo is characterized as solitary phagotrophic flagellates with a single discrete eukinetoplast. They are known for having an apical cytostome and cytopharynx supported by a prismatic rod of microtubules. Neobodo cells are usually elongate and elliptical in shape and somewhat inflexible. They range from 4 to 12 microns long, but are mostly 6 to 9 microns.
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Yellow-green algae or the Xanthophyceae (xanthophytes) are an important group of heterokont algae. Most live in fresh water, but some are found in marine and soil habitats. They vary from single-celled flagellates to simple colonial and filamentous forms. Xanthophyte chloroplasts contain the photosynthetic pigments chlorophyll a, chlorophyll c, β-carotene, and the carotenoid diadinoxanthin.
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The prasinophytes are morphologically diverse, including flagellates with one to eight flagella and non-motile (coccoid) unicells. The cells of many species are covered with organic body scales; others are naked. Well studied genera include Ostreococcus, considered to be the smallest (ca. 0.95 μm) free-living eukaryote, and Micromonas, both of which are found in marine waters worldwide.
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The diplomonads (Greek for "two units") are a group of flagellates, most of which are parasitic. They include Giardia lamblia, which causes giardiasis in humans. They are placed among the metamonads, and appear to be particularly close relatives of the retortamonads. Most diplomonads are double cells: they have two nuclei, each with four associated flagella, arranged symmetrically about the body's main axis.
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Kraken is a recently discovered genus, having first been described in 2016 at the University of Koln. Thomas Cavalier-Smith established the phylum Cercozoa in 1998, which consists of flagellates and filose amoebae that are widely morphologically diverse. Genetic analysis and morphological characteristics place the Genus Kraken as a Cercozoan. Currently, the genus consists of a single species, Kraken carinae.
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Mesofauna contribute to habitable pore spaces and account for a small portion of total pore spaces. Clay soils have much smaller particles which reduce pore space. Organic material can fill small pores. Grazing of bacteria by bacterivorous nematodes and flagellates, soil mesofauna living in the pores, may considerably increase Nitrogen mineralization because the bacteria are broken down and the nitrogen is released.
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Free-living cells can show a variety of morphologies, depending on the species. All species can exist as scaled flagellates, and this is the only form that has been observed for P. scrobiculata and P. cordata. Three species have been observed as colonies (P. globosa, P. pouchetii and P. antarctica) and these can also exist as a flagellate devoid of scales and filaments.
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Examples of species within this group are H. ovale and H. exaratum. The skidding behaviour is very similar to the primary osmotrophs, where the motion is powered by the beating of the anterior flagellum, positioned in a curve to the right of the cell, in a sinusoidal pattern.Larsen, Jacob; Patterson, David J. (1990). “Some flagellates (Protista) from tropical marine sediments”.
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Picoplankton also form the base of aquatic microbial food webs and are an energy source in the microbial loop. All trophic levels in a marine food web are affected by picoplankton carbon production and the gain or loss of picoplankton in the environment, especially in oligotrophic conditions. Marine predators of picoplankton include heterotrophic flagellates and ciliates. Protozoa are a dominant predator of picoplankton.
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In addition, flagellates contribute substantially to biodiversity, but their species number is unknown. Protozoan and metazoan ice meiofauna, in particular turbellarians, nematodes, crustaceans and rotifers, can be abundant in all ice types year- round. In spring, larvae and juveniles of benthic animals (e.g. polychaetes and molluscs) migrate into coastal fast ice to feed on the ice algae for a few weeks.
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S. roeselii is found in still or slow-moving bodies of water, where it feeds on bacteria, flagellates, algae, and other ciliates. When feeding, the cell is fixed in place (sessile), attached by a posterior "holdfast" organelle to a firm surface such as plant stem or submerged detritus. Attached specimens are trumpet-shaped, and very contractile. When swimming freely, cells are compactly ovoid.
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Colponema is a genus of single-celled flagellates that feed on eukaryotes in aquatic environments and soil. The genus contains 6 known species and has not been thoroughly studied. Colponema has two flagella which originate just below the anterior end of the cell. One extends forwards and the other runs through a deep groove in the surface and extends backwards.
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Colponema is a predator that feeds on smaller flagellates using its ventral groove. Like many other alveolates, they possess trichocysts, tubular mitochondrial cristae, and alveoli. It has been recently proposed that Colponema may be the sister group to all other alveolates. The genus could help us understand the origin of alveolates and shed light on features that are ancestral to all eukaryotes.
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Usually, the amoeboid form is taken when food is plentiful, and the flagellate form is used for rapid locomotion. However, not all members are able to assume both forms. The genera Percolomonas, Lyromonas, and Psalteriomonas are known only as flagellates, while Vahlkampfia, Pseudovahlkampfia, and most acrasids do not have flagellate stages. As mentioned above, under unfavourable conditions, the acrasids aggregate to form sporangia.
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Trachelomonads are free- swimming, solitary, photosynthetic flagellates ranging in size from 5-100um, with an ovoid shape, sharing similar morphological characteristics with its sister group, Strombomonas.Brosnan, Stacy; Brown, Patrick J.; Farmer, Mark A.; Triemer, Richard E. (2005). “Morphological separation of the euglenoid genera Trachelomonas and Strombomonas (Euglenophyta) based on lorica development and posterior strip deduction”. Journal of Phycology. 41 (3): 590-605.
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Also, only some species are flagellates, and when they do have flagella, have only two basal body rings to support them, whereas gram-negative have four. Both gram- positive and gram-negative bacteria commonly have a surface layer called an S-layer. In gram-positive bacteria, the S-layer is attached to the peptidoglycan layer. Gram-negative bacteria's S-layer is attached directly to the outer membrane.
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Oda et al. found that differences in the production of ROS were due to the size of the cell. By comparing four species of flagellates, they showed that the larger species Ichatonella produced the most superoxide and hydrogen peroxide per cell than Heterosigma akashiwo, Olisthodiscus luteus, and Fibrocapsa japonica. In a comparison of 37 species of marine microalgae, including dinoflagellates, rhaphidophytes, and chlorophytes, Marshall et al.
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Although there is a core microbiome shared among castes and colonies, the alate caste gut is characterised by a significantly lower abundances of bacteria in the genus Treponema (Spirochaetes) and the class Endomicrobia (Elusimicrobia) compared to workers and soldiers. Flagellates in the class Parabasalia and the order Oxymonadida are also significantly less abundant in the alate gut, with the latter significantly reduced in dealates as well.
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Organisms traditionally classified as protozoa are abundant in aqueous environments and soil, occupying a range of trophic levels. The group includes flagellates (which move with the help of whip-like structures called flagella), ciliates (which move by using hair-like structures called cilia) and amoebae (which move by the use of foot-like structures called pseudopodia). Some protozoa are sessile, and do not move at all.
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In contrast to certain other species of the genus, Mesodinium chamaeleon can be maintained in culture for short periods only. It captures and ingests flagellates including cryptomonads. The prey is ingested very rapidly into a food vacuole without the cryptomonad flagella being shed and the trichocysts being discharged. The individual food vacuoles subsequently serve as photosynthetic units, each containing the cryptomonad chloroplast, a nucleus, and some mitochondria.
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In flagellates and ciliates, the position of the flagellum or cilium is determined by the mother centriole, which becomes the basal body. An inability of cells to use centrioles to make functional flagella and cilia has been linked to a number of genetic and developmental diseases. In particular, the inability of centrioles to properly migrate prior to ciliary assembly has recently been linked to Meckel–Gruber syndrome.
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Botanists subsequently created the algal division Euglenophyta; thus, they were classified as both animals and plants, as they share characteristics with both. Conflicts of this nature are exemplary of why the kingdom Protista was adopted. However, they retained their double-placement until the flagellates were split up, and both names are still used to refer to the group. Their chlorophylls are not masked with accessory pigments.
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P. psammophila is a filter feeder and the lophophore is used in both feeding and respiration. It is orientated so that it faces the prevailing water current. Cilia on the inside of the tentacles create a feeding current and draw in particles. The diet consists of diatoms, microalgae, flagellates, invertebrate larvae and detritus and these are caught and transported to the mouth by the cilia.
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Provasoli attended the University of Milan and earned his degree in 1931. He continued his studies into protozoa, silkworms and flagellates, and received his Ph.D in zoology in 1939. After his graduation, he worked in the lab of Andre Lwoff at the Pasteur Institute in Paris and developed a deep interest in algae. In 1942, he was appointed Professor at the University of Camerino.
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Infested fish may exhibit loss of appetite and slowed growth, and behavioral signs such as erratic swimming and rubbing up against aquarium walls. The damage and infection cause stress and mortality. The common fish louse is also a vector for pathogens, introducing organisms such as bacteria, flagellates, and the virus that causes spring viraemia of carp. It is an intermediate host to nematodes of the family Skrjabillanidae.
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In addition to mammals, several insects are also hindgut fermenters, the best studied of which are the termites, which are characterised by an enlarged "paunch" of the hindgut that also houses the bulk of the gut microbiota. Digestion of wood particles in lower termites is accomplished inside the phagosomes of gut flagellates, but in the flagellate- free higher termites, this appears to be accomplished by fibre-associated bacteria.
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Primary flagellates form directly from trophozoites and tend to initially present as spheres and slowly assume a more ovoid shape while often slightly flattening posteriorly as they become motile. During the maturation of the flagellated stage, the flagella emerge in 2 pairs. By the time the cell is approximately half of its mature size, the four flagella are equal in length. Like the amoeboid stage, they are capable of asexual division.
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During summers phytoplankton are dominated by cyanobacteria and occasionally diatoms, most commonly Aphanizomenon cf gracile but also Pseudanabaena limnetica, Planktolyngbya sp. and various species of Anabaena, of whom only Aphanizomenon is potentially poisonous and Anabaena frequently causes algal bloom. Carapace flagellates such as Ceratium hirundinella and various dinoflagellates, are few but important to the lake's biomass. Various rotifers are common zooplankton but cyclopoid copepods can also be found.
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It gets its name from the combination of "Sarcodina" (which is an older term used for amoeboids) and "Mastigophora" (which is an older term for flagellates). The characteristics of phylum sarcomastigophora are : (1) Nucleus is of one type except in the stages of certain foraminifera. (2) Locomotory organ either pseudopodia or flagella or both. (3) Reproduction asexual , but when sexually it is essentially by _syngamy_ (4) Spore formation is absent.
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However, Thalis pauses to strip Natala of her tunic and, with a jewel-handled whip, flagellates the Brythunian. In the middle of this bizarre act, Thog suddenly appears, snatches Thalis, and devours her. The demon returns for Natala, but Conan intervenes and saves her. Conan fights Thog with all his might, but is scarcely harming the demon's supernatural form, while receiving hideous wounds in the coils of its pseudopods and tentacles.
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Minerals can be bioengineered by bacteria which act on metals to catalyze mineral dissolution and precipitation. Mineral nutrients are recycled by bacteria distributed throughout soils, oceans, freshwater, groundwater, and glacier meltwater systems worldwide. Bacteria absorb dissolved organic matter containing minerals as they scavenge phytoplankton blooms. Mineral nutrients cycle through this marine food chain, from bacteria and phytoplankton to flagellates and zooplankton, which are then eaten by other marine life.
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Ernst Haeckel, in his 1866 Generelle Morphologie der Organismen, asserted that all living things were monophyletic (had a single evolutionary origin), being divided into plants, protista, and animals. His protista were divided into moneres, protoplasts, flagellates, diatoms, myxomycetes, myxocystodes, rhizopods, and sponges. His animals were divided into groups with distinct body plans: he named these phyla. Haeckel's animal phyla were coelenterates, echinoderms, and (following Cuvier) articulates, molluscs, and vertebrates.
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Spironema multiciliatum Spironemidae is a family of heterotrophic flagellates, in the group Hemimastigophora. They vary in size and shape from the ellipsoid Hemimastix amphikineta (14 × 7 μm) to the vermiform Spironema terricola (43 × 3 μm), and are united by the possession of two rows of cilia, called kineties. Phylogenomic analysis shows that Hemimastigophora are a distinct and ancient lineage of eukaryotic organisms, forming a possible sister clade to the supergroup Diaphoretickes.
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The size of the cells within the genus range from 14 to 170 micrometres in length and 7 to 46 micrometers in width. Unlike other anaerobic flagellates, members of the genus Saccinobaculus rarely contain bacterial symbionts on their surface. Some species of Saccinobacculus have evenly-distributed concavities on their surface. The shape of the cell is variable and can take the form of a sphere to an elongated rod.
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Alongside with the variations of meiosis related to the moment when meiosis occur in life cycles, resulting in post- zygotic, pre-gametic and intermediate meiosis (see above), the number of nuclear divisions in meiosis is also variable. The majority of eukaryotes have a two-divisional meiosis (though sometimes achiasmatic), but a very rare form, one-divisional meiosis, occurs in some flagellates (parabasalids and oxymonads) from the gut of the wood-feeding cockroach Cryptocercus.
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The best-known Cercozoa are the euglyphids, filose amoebae with shells of siliceous scales or plates, which are commonly found in soils, nutrient-rich waters, and on aquatic plants. Some other filose amoebae produce organic shells, including the tectofilosids and Gromia. They were formerly classified with the euglyphids as the Testaceafilosia. This group is not monophyletic, but nearly all studied members fall in or near the Cercozoa, related to similarly shelled flagellates.
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Choanoflagellates, also called "collar-flagellates" are unicellular protists that exist in both freshwaters and oceans. Choanoflagellates have a spherical (or ovoid) cell body and a flagellum that is surrounded by a collar composed of actin microvilli. The flagellum is used to facilitate movement and food intake. As the flagellum beats, it takes in water through the microvilli attached to the collar, which helps filter out unwanted bacteria and other tiny food particles.
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Though mostly complete the exuvia is missing the right foreleg, the left middle leg, a small section of antenna and the anteocular region. Triatoma dominicana is the first extinct Triatominae species to be described from the fossil record. Included in the amber specimen are two fecal pellets from the insect which contain preserved flagellates of the extinct Trypanosoma antiquus. This association is the oldest known example of the vector association between Triatoma and Trypanosoma.
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After a priest determines Danila may be possessed, she is taken to a remote Catholic convent in the mountains to undergo an exorcism. When the nuns recite Latin prayer in the chapel, Danila goes mad and flees, but is stopped in town. Sequestered in the mother's superior's quarters, Danila is approached by Father Xeno, a priest, and she attempts to seduce and fellate him. In his room, Father Xeno flagellates himself as penance.
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In summers, phytoplankton algae are dominated by cyanobacteria and some carapace flagellates. Other species have been abundant, but today only a single nitrogen fixating algae is present in the lake. During winters and springs, Planktothrix agardhii adopt a red colour which occasionally colours the lake in shades of red and brown. Larger zooplankton include water fleas (Bosmina) and copepods (Daphnia); and smaller species, rotifers, seem to have increased during the later part of the 1990s.
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The retortamonads are a small group of flagellates, most commonly found in the intestines of animals as commensals, although a free-living species called the Chilomastix cuspidata exists. They are grouped under the taxon, Archezoa. They are usually around 5-20 μm in length, and all of their small subunit ribosomal RNA gene sequences are very similar to each other. There are two genera: Retortamonas with two flagella, and Chilomastix with four.
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Amoebae are larger than flagellates and move in a different way. Amoebae can be distinguished from other protozoa by their slug-like properties and pseudopodia. A pseudopodium or “false foot” is a temporary obtrusion from the body of the amoeba that helps pull it along surfaces for movement or helps to pull in food. The amoeba does not have permanent appendages and the pseudopodium is more of a slime-like consistency than a flagellum.
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Cell scheme Each choanoflagellate has a single flagellum, surrounded by a ring of actin-filled protrusions called microvilli, forming a cylindrical or conical collar (choanos in Greek). Movement of the flagellum draws water through the collar, and bacteria and detritus are captured by the microvilli and ingested. Water currents generated by the flagellum also push free- swimming cells along, as in animal sperm. In contrast, most other flagellates are pulled by their flagella.
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However, the importance of competition is also demonstrated by the production of phycotoxins that negatively impact other phytoplankton species. Flagellates (especially dinoflagellates) are the principle producers of phycotoxins; however, there are known toxigenic diatoms, cyanobacteria, prymnesiophytes, and raphidophytes. Because many of these allelochemicals are large and energetically expensive to produce, they are synthesized in small quantities. However, phycotoxins are known to accumulate in other organisms and can reach high concentrations during algal blooms.
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Between 1895 and 1898 he worked as a pharmacist in German East Africa. He was an early assistant to Bernhard Nocht at the Institut für Tropenmedizin in Hamburg, where in 1900 he became head of the Department of Chemistry. In 1904 Giemsa published an essay on the staining procedure for flagellates, blood cells, and bacteria. Giemsa improved the Romanowsky stain (Eosin Y and Methylene Blue) by stabilizing this dye solution with glycerol.
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In the Northwestern Mediterranean, the most abundant phytoplankton present are coccolithophorids, flagellates, and dinoflagellates. The Southeastern Mediterranean has a similar composition, where coccolithophorids and monads (nano- and picoplankton) make up the majority of the phytoplankton community in the DCM. In the Indian Ocean, the most abundant microorganisms present in the DCM are cyanobacteria such as prochlorophytes, coccolithophorids, dinoflagellates and diatoms. In the North Sea, dinoflagellates are the main phytoplankton species present in the DCM at and below the pycnocline.
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This placement suggests that the fly struggled to free itself from the resin when first trapped. Found preserved in the proboscis and alimentary tract of the fly were hundreds of trypanosomatid parasites of the species Paleoleishmania neotropicum. During the struggle the fly ruptured her alimentary tract, which allowed some of the flagellates in the gut to leak into the hemocoel. The species P. neotropicum described from these fossils is the second known occurrence for this parasitic genus.
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The efficiency of the microbial loop is determined by the density of marine bacteria within it. It has become clear that bacterial density is mainly controlled by the grazing activity of small protozoans and various taxonomic groups of flagellates. Also, viral infection causes bacterial lysis, which release cell contents back into the dissolved organic matter (DOM) pool, lowering the overall efficiency of the microbial loop. Mortality from viral infection has almost the same magnitude as that from protozoan grazing.
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Coleps feeds on bacteria, algae, flagellates, living and dead ciliates, animal and plant tissues. Coleps uses toxicysts, which are organelles containing poison that it uses to capture its prey from its oral area. It extrudes tube-like structures to force toxicysts into its prey and wait until its prey becomes paralyzed. These toxicysts, however, takes about 5–10 minutes to be effective on the prey of the Coleps and it separates itself from the prey during this time.
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A colony starts when a larva settles on a suitable surface and undergoes metamorphosis into an ancestrula. This forms daughter zooids by budding and the colony grows by asexual reproduction. In common with other bryozoans, Electra pilosa filter feeds with the aid of a crown of tentacles known as a lophophore with which it sieves particles from the water. It probably feeds on such things as flagellates, phytoplankton, bacteria, small pieces of algal debris and algal spores.
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The green algae are a large group of photosynthetic eukaryotes that include many microscopic organisms. Although some green algae are classified as protists, others such as charophyta are classified with embryophyte plants, which are the most familiar group of land plants. Algae can grow as single cells, or in long chains of cells. The green algae include unicellular and colonial flagellates, usually but not always with two flagella per cell, as well as various colonial, coccoid, and filamentous forms.
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There are about twenty broad white radially arranged septa (ridges) joined to the corallite wall, with secondary septa between. They have large, rounded lobes and the central axial structure (columella) in the corallite is short and broad. The septa can be seen through the transparent, fleshy mantle which contains symbiotic flagellates known as zooxanthellae which give the coral its colour. This is usually pale brown or green, sometimes with a contrasting oral disc, but also sometimes pinkish or bluish.
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In both cases there are four basal bodies anterior to a prominent feeding groove, and one flagellum is directed back through the cell, emerging from the groove. The retortamonads lack mitochondria, golgi apparatus, dictyosomes, and peroxisomes. They are close relatives of the diplomonads, and are placed among the metamonads along with them. Due to the abundant phylogenetic similarities between the two flagellates, since diplomonads do not ancestrally lack mitochondrion, this suggests that retortamonads are also secondarily amitochondriate.
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Throughout the numerous oceans, large fractions of small heterotrophic flagellates with few morphological features remain unidentified. Therefore there is a high possibility that there are many bodonids among the unidentified that have not yet been studied. Although Neobodo are surface organisms, typically found in surface waters, studies have shown their ability to tolerate deep water conditions. Due to advection or attachment to sinking particles, microbes from the surface of the ocean are continuously transported to deeper areas.
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Since the realization that the embryophytes emerged from within the green algae, some authors are starting to include them. The clade that includes both green algae and embryophytes is monophyletic and is referred to as the clade Viridiplantae and as the kingdom Plantae. The green algae include unicellular and colonial flagellates, most with two flagella per cell, as well as various colonial, coccoid and filamentous forms, and macroscopic, multicellular seaweeds. There are about 8,000 species of green algae.
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Peranema is a genus of free-living phagotrophic euglenids (Euglenida; Euglenozoa; Excavata). There are more than 20 nominal species, varying in size between 8 and 200 micrometers. Peranema cells are gliding flagellates found in freshwater lakes, ponds and ditches, and are often abundant at the bottom of stagnant pools rich in decaying organic material. Although they belong to the class Euglenoidea, and are morphologically similar to the green Euglena, Peranema have no chloroplasts, and do not conduct autotrophy.
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Although Rhodelphis only contains two known species, both were isolated from very different aquatic habitats. R. marinus was found in Vietnam inhabiting coral sand in the shallow waters off the coast of a small island, Bay Canh. The other species, R. limneticus, was found in a freshwater sample from Lake Trubin in the Ukraine, living among debris. Rhodelphis is a heterotrophic predator that feeds on bacteria and smaller flagellates, but little is known about its role in aquatic ecosystems.
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Despite its lack of thecal plates, a prominent feature helpful in identifying armored flagellates, A. sanguinea is relatively large and easily recognizable. Like most dinoflagellates, one flagellum is complex, wrapping around the equator of the cell in a groove. The other flagellum extends out from the cell to help aid its movement through the water. A. sanguinea’s most prominent features are the lack of a nuclear envelope chamber and the apical groove's large, clockwise path when viewed from the front of the cell.
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A flagellum (; plural: flagella) is a lash-like appendage that protrudes from the cell body of certain bacteria and eukaryotic cells termed as flagellates. A flagellate can have one or several flagella. The primary function of a flagellum is that of locomotion, but it also often functions as a sensory organelle, being sensitive to chemicals and temperatures outside the cell. The similar structure in the archaea functions in the same way but is structurally different and has been termed the archaellum.
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During the fly's struggle to escape from the resin, the alimentary tract was ruptured and some P. neotropicum flagellates leaked from there into the hemocoel. P. neotropicum and L. adiketis lived in an environment similar to modern moist tropical rain forests. The morphology of the compact kinetoplast, nucleus, and rear-facing flagellum indicate the species belongs in the family Trypanosomatidae. The preserved amastigotes are between 4 and 7 µm and their presence in the fly indicates the digenetic nature of the species.
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Mackinnon published over 40 academic papers, primarily on parasitic species of protozoa (especially flagellates and sporozoa). She had a reputation for her skill as a lecturer, which stemmed from her time at University College, Dundee. Mackinnon gave broadcast talks for schools and numerous lectures, with a reputation that she never repeated a lecture in 30 years of teaching. These included lectures on the diseases spread by flies, and how good hygiene and the prevention of flies breeding could stop typhoid.
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Entamoeba belongs to the Archamoebae, which like many other anaerobic eukaryotes have reduced mitochondria. This group also includes Endolimax and Iodamoeba, which also live in animal intestines and are similar in appearance to Entamoeba, although this may partly be due to convergence. Also in this group are the free-living amoebo-flagellates of the genus Mastigamoeba and related genera. Certain other genera of symbiotic amoebae, such as Endamoeba, might prove to be synonyms of Entamoeba but this is still unclear.
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Members of the Hemitrichia follow the typical plasmodial slime mold life cycle, which exhibits two main stages as well as possible sexual reproduction. Slime molds spend a period of their life cycle as a myxameoba or a swarm cells. These cells are able to exist as either amoeba or flagellates depending on the conditions the cell experiences, and are hence known as amoeboflagellates. The amoeba form is preferred for terrestrial environments, while the swimming ability of flagella is preferred in a wet environment.
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The external appearance of the giant northern termite Mastotermes darwiniensis is suggestive of the close relationship between termites and cockroaches. Termites were formerly placed in the order Isoptera. As early as 1934 suggestions were made that they were closely related to wood-eating cockroaches (genus Cryptocercus, the woodroach) based on the similarity of their symbiotic gut flagellates. In the 1960s additional evidence supporting that hypothesis emerged when F. A. McKittrick noted similar morphological characteristics between some termites and Cryptocercus nymphs.
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Melkonian has research interests that range from cell biology, Melkonian, M., Robenek, H. (1980): Eyespot membranes of Chlamydomonas reinhardii: a freeze-fracture study. J. Ultrastruct. Res. 72, 90-102Salisbury, J.L., Baron, A., Surek, B., Melkonian, M. (1984): Striated flagellar roots: isolation and partial characterization of a calcium-modulated contractile organelle. J. Cell Biol. 99, 962-970 Melkonian, M., Reize, I.B., Preisig, H.R. (1987): Maturation of a flagellum/basal body requires more than one cell cycle in algal flagellates: Studies on Nephroselmis olivacea (Prasinophyceae).
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In 1997, Richard Triemer returned to the subject, to confirm Chen's opinion that Peranema has a dual feeding technique. It can swallow prey whole, pulling large flagellates through the cytostome, in a manner similar to that proposed by Brenda Nisbet. However, it can also choose a more elaborate style of attack. Sometimes, it will press its cytostome against its prey, and then move the rod-organ up and down, using a rasping motion to chew a hole in its victim's cell membrane.
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William Trager was born March 20, 1910 in Newark, New Jersey to Leon and Anna (Emilfork) Trager. He received his bachelor of science degree from Rutgers University in 1930. He then moved to Harvard University where he was the first graduate student of L. R. Cleveland. In Cleveland's lab, Trager established a culture system for flagellate symbionts of the roach Cryptocercus punctulatus, showing that the roach's ability to digest cellulose was actually due to the cellulases of the symbiotic flagellates.
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All animals are posited by biologists to have evolved from a flagellated eukaryote. Their closest known living relatives are the choanoflagellates – collared flagellates whose cell morphology is similar to the choanocyte cells of certain sponges. Molecular studies place animals in a supergroup called the opisthokonts, which also include the choanoflagellates, fungi, and a few small parasitic protists. The name comes from the posterior location of the flagellum in motile cells, such as most animal spermatozoa, whereas other eukaryotes tend to have anterior flagella.
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Losses of bacterioplankton by grazing is indirectly related to carbon balances and directly related to prokaryotic inhibitors. A surplus of substrate would cause increased flagellate biomass, increased grazing on bacterioplankton and therefore decreased bacterial biomass overall. Predation of ciliates is analogous to predation by flagellates on bacteria as well. With using prokaryotic inhibitors seasonally, there is a positive relationship between bacterial abundance and heterotrophic nanoplankton grazing rates and only 40-45 % of bacterioplankton production was observed to be consumed by phagotrophic Protozoa.
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When exposed to light, the starving plasmodium differentiates irreversibly into sporangia that are distinguished from other Physarum species by their multiple heads (hence polycephalum). Meiosis occurs during spore development, resulting in haploid dormant spores. Upon exposure to moist nutrient conditions, the spores develop into amoebae, or, in aqueous suspension, into flagellates. The life cycle is completed when haploid amoebae of different mating types fuse to form a diploid zygote that then develops by growth and nuclear division in the absence of cytokinesis into the multinucleate plasmodium.
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Climacostomum gigas is reported to have a compact, ovoid macronucleus. The cell's most prominent feature is its large oral apparatus, which occupies most of the anterior region. This structure features an adoral zone of membranelles (AZM) partly encircling a wide oral cavity which opens into the cytopharyngeal pouch where digestive vacuoles are formed before they travel down the long, bent cytopharyngeal tube into the body of the cell. Climacostomum is found in fresh or brackish water, and feeds on suspended particles, such as bacteria and small flagellates.
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Researchers have collected and analyzed molecular data from 13 prasinophyte taxa to better construct the phylogenetic relationship of early branching green alga.Nakayama, T., Marin, B., Kranz, H.D., Surek, B., Huss, V.A., Inouye, I. and Melkonian, M. 1998: The Basal Position of Scaly Green Flagellates among the Green Algae (Chlorophyta) is Revealed by Analyses of Nuclear-Encoded SSU rRNA Sequences. Protistology. 149: 367-380. 10.1016/S1434-4610(98)70043-4 Phylogenetic analysis of the small subunit ribosomal-RNA sequence was performed using distance, parsimony, and likelihood statistical tests.
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The term protista was first used by Ernst Haeckel in 1866. Protists were traditionally subdivided into several groups based on similarities to the "higher" kingdoms such as: ;Protozoa: These unicellular "animal-like" (heterotrophic, and sometimes parasitic) organisms are further sub-divided based on characteristics such as motility, such as the (flagellated) Flagellata, the (ciliated) Ciliophora, the (phagocytic) amoeba, and the (spore-forming) Sporozoa. ;Protophyta: These "plant-like" (autotrophic) organisms are composed mostly of unicellular algae. The dinoflagelates, diatoms and Euglena-like flagellates are photosynthetic protists.
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In the early 20th century, phytoplankton was dominated by green algae, diatoms, and carapace flagellates with a smaller amount of cyanobacteria, a normal distribution for lakes rich in nutrients. By 2000, the biomass was almost exclusively composed of cyanobacteria, most of them non-poisonous "thin filaments" and anabacena the only species being able to fixate nitrogen. Today, the only reminder of the 1990s is the relatively frequent occurrence of the carapace flagellate Ceratium hirundinella. Zooplankton, moderate levels of rotifers and copepods, have shown insignificant variations with time.
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Over the rest of the cell, except for a diminished mouth called the micropore, the membrane is supported by vesicles called alveoli, forming a semirigid pellicle. The presence of alveoli and other traits place the Apicomplexa among a group called the alveolates. Several related flagellates, such as Perkinsus and Colpodella, have structures similar to the polar ring and were formerly included here, but most appear to be closer relatives of the dinoflagellates. They are probably similar to the common ancestor of the two groups.
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This hypothesis was originally based on similarity of the symbiotic gut flagellates in termites regarded as living fossils and wood- eating cockroaches. Additional evidence emerged when F. A. McKittrick (1965) noted similar morphological characteristics between some termites and cockroach nymphs. The similarities among these cockroaches and termites have led some scientists to reclassify termites as a single family, the Termitidae, within the order Blattodea. Other scientists have taken a more conservative approach, proposing to retain the termites as the Termitoidae, an epifamily within the order.
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The choanoflagellates are a group of free-living unicellular and colonial flagellate eukaryotes considered to be the closest living relatives of the animals. Choanoflagellates are collared flagellates having a funnel shaped collar of interconnected microvilli at the base of a flagellum. Choanoflagellates are capable of both asexual and sexual reproduction. They have a distinctive cell morphology characterized by an ovoid or spherical cell body 3–10 µm in diameter with a single apical flagellum surrounded by a collar of 30–40 microvilli (see figure).
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Saccinobaculus is a genus of symbiotic flagellates that live exclusively in the hindgut of the wood-feeding cockroach Cryptocercus punctulatus. Saccinobaculus is found in great numbers and diversity in the hindgut of C. punctulatus and plays a role in the digestion of wood materials that the insect-host feeds on. The mode of nutrition and the specific role of Saccinobaculus in the digestion of wood materials within its insect-host remains poorly understood. This may be due to its resistance to cultivation in a laboratory settings.
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Ehrenberg was appointed professor of medicine at Berlin University in 1827. In 1829 he accompanied Humboldt through eastern Russia to the Chinese frontier. After his return he began to concentrate his studies on microscopic organisms, which until then had not been systematically studied. For nearly 30 years Ehrenberg examined samples of water, soil, sediment, blowing dust and rock and described thousands of new species, among them well-known flagellates such as Euglena, ciliates such as Paramecium aurelia and Paramecium caudatum, and many fossils, in nearly 400 scientific publications.
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Acetate is the main energy source for lower termites and wood roaches, so without the activity of Trichonympha, its host would not be able to survive. Higher termites likely do not have flagellates, such as Trichonympha, in their hindgut because they have diversified their diet to include food sources other than wood. The large quantities of hydrogen produced while sugar is converted into the energy for the host’s use causes the hindgut of lower termites and wood roaches to be highly anoxic. This creates a very hospitable environment for Trichonympha as it is anaerobic.
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The group includes most amoeboids and flagellates that feed by means of filose pseudopods. These may be restricted to part of the cell surface, but there is never a true cytostome or mouth as found in many other protozoa. They show a variety of forms and have proven difficult to define in terms of structural characteristics, although their unity is strongly supported by genetic studies. Cercozoa are closely related to Foraminifera and Radiolaria, amoeboids that usually have complex shells, and together with them form a supergroup called the Rhizaria.
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When the lophophore is extended, cilia (little hairs) on the sides of the tentacles draw water down between the tentacles and out at the base of the lophophore. Shorter cilia on the inner sides of the tentacles flick food particles into a groove in a circle under and just inside the tentacles, and cilia in the groove push the particles into the mouth. Phoronids direct their lophophores into the water current, and quickly reorient to maximize the food-catching area when currents change. Their diet includes algae, diatoms, flagellates, peridinians, small invertebrate larvae, and detritus.
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Retinylidene protein, is a family of proteins that use retinal as a chromophore for light reception. It is the molecular basis for a variety of light-sensing systems from phototaxis in flagellates to eyesight in animals. Retinylidene proteins include all forms of opsin and rhodopsin (in the broad sense). While rhodopsin in the narrow sense refers to a dim-light visual pigment found in vertebrates, usually on rod cells, rhodopsin in the broad sense (as used here) refers any molecule consisting of an opsin and a retinal chromophore in the ground state.
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Lwoff was born in Ainay-le-Château, Allier, in Auvergne, France, the son of Marie (Siminovitch), an artist, and Solomon Lwoff, a psychiatrist. He joined the Institute Pasteur in Paris when he was 19 years old. In 1932, he finished his PhD and, with the help of a grant from the Rockefeller Foundation, moved to the Kaiser Wilhelm Institute for Medical Research of Heidelberg to Otto Meyerhof, where he did research on the development of flagellates. Another Rockefeller grant allowed him go to the University of Cambridge in 1937.
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Primary consumers rely upon primary production as a main food source. The most important consumers of the pelagic web of the LSZ are copepods, along with the rotifers, flagellates and ciliates mentioned above. All species of calanoid copepods have declined under high predation pressure from the recently introduced Amur River clam (Corbula amurensis). Because of this, and because copepods rely upon both photosynthetic and detrital food sources, copepods in the LSZ have limited feedback on primary production, unlike marine and lentic systems where copepods can graze down blooms in a matter of days.
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The microbial food web refers to the combined trophic interactions among microbes in aquatic environments. These microbes include viruses, bacteria, algae, heterotrophic protists (such as ciliates and flagellates).Mostajir B, Amblard C, Buffan-Dubau E, De Wit R, Lensi R, Sime-Ngando T. (2015) "Microbial food webs in aquatic and terrestrial ecosystems" In: Bertrand J-C, Caumette P, Lebaron P, Matheron R, Normand P and Sime-Ngando T (Eds.) Environmental Microbiology: Fundamentals and Applications: Microbial Ecology pages 485–510, Springer. . In aquatic environments, microbes constitute the base of the food web.
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The highest concentration of flagellates in these insects is found in the pylorus region of this vector which may be important to transmission to the host. E. schaudinni is an intracellular parasite which invades the red blood cells of its definitive host. Little research has been done on the mechanism of action of this or the benefit of residing in the red blood cells but antigenic masking seems a possible reason. E. schaudinni is a hemoflagellate with a size of about 13.5 µm in length and 3.5 µm in diameter.
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Size and distribution of phytoplankton are also related to fronts. Microphytoplankton (>20μm) are found at fronts and at sea ice boundaries, while nanophytoplankton (<20μm) are found between fronts. Studies of phytoplankton stocks in the southern sea have shown that the Antarctic Circumpolar Current is dominated by diatoms, while the Weddell Sea has abundant coccolithophorids and silicoflagellates. Surveys of the SW Indian Ocean have shown phytoplankton group variation based on their location relative to the Polar Front, with diatoms dominating South of the front, and dinoflagellates and flagellates in higher populations North of the front.
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Neobodo are diverse protists belonging to the eukaryotic supergroup Excavata. They are Kinetoplastids in the subclass Bodonidae. They are small, free- living, heterotrophic flagellates with two flagella of unequal length used to create a propulsive current for feeding.Kirchman, D. 2008: Microbial ecology of the oceans / [edited by] David L. Kirchman. (2nd ed.).As members of Kinetoplastids, they have an evident kinetoplast Tikhonenkov, D. V., Janouškovec, J., Keeling, P. J., and Mylnikov, A. P. 2016: The Morphology, Ultrastructure and SSU rRNA Gene Sequence of a New Freshwater Flagellate, Neobodo borokensis n. sp.
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However, the plastids are very different from red algal plastids: phycobiliproteins are present but only in the thylakoid lumen and are present only as phycoerythrin or phycocyanin. In the case of Rhodomonas, the crystal structure has been determined to 1.63Å; and it has been shown that the alpha subunit bears no relation to any other known phycobiliprotein. A few cryptomonads, such as Cryptomonas, can form palmelloid stages, but readily escape the surrounding mucus to become free-living flagellates again. Some Cryptomonas species may also form immotile microbial cysts—resting stages with rigid cell walls to survive unfavorable conditions.
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During the spring months, the DCM coincides with the upper surface of the nitracline, making the water nutrient-rich for diatoms Cyclotella striata and crysophytes Dinobryon bavaricum to thrive in. During the summer months, the DCM deepens, and productivity within the layer almost becomes entirely light dependent. Similar to the chlorophyll structures found in oceans, the DCM becomes incredibly fluid and variable, such that certain phytoplankton species (diatoms Synedra ulna, Cyclotella comta and green flagellates) begin to dominate, despite being absent during the spring productivity period. Overall, the phytoplankton community between the epilimnion and the DCM in Lake Tahoe differ with size.
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However, the plastids are very different from red algal plastids: phycobiliproteins are present but only in the thylakoid lumen and are present only as phycoerythrin or phycocyanin. In the case of "Rhodomonas" the crystal structure has been determined to 1.63Å; and it has been shown that the alpha subunit bears no relation to any other known phycobiliprotein. A few cryptophytes, such as Cryptomonas, can form palmelloid stages, but readily escape the surrounding mucus to become free-living flagellates again. Some Cryptomonas species may also form immotile microbial cysts–resting stages with rigid cell walls to survive unfavorable conditions.
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Lake Van viewed from space shuttle Challenger during flight STS-41-G The only fish known to live in the brackish water of Lake Van is Chalcalburnus tarichi or Pearl Mullet (), a Cyprinid fish related to chub and dace, which is caught during the spring floods. In May and June, these fish migrate from the lake to less alkaline water, spawning either near the mouths of the rivers feeding the lake or in the rivers themselves. After spawning season it returns to the lake. 103 species of phytoplankton have been recorded in the lake including cyanobacteria, flagellates, diatoms, green algae, and brown algae.
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Spirochaetes and flagellates from a R. flavipes gut Most bacterial species in the termite gut are difficult or impossible to culture, so methods like 16S ribosomal RNA sequencing are used to identify which groups are present. One such analysis of R. flavipes worker guts uncovered representatives of the Endomicrobia (Elusimicrobia), Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes, and Spirochaetes. The dominant bacterial taxon in the core gut microbiome is the genus Treponema (Spirochaetes), which accounted for approximately 32% of sequences in another 16S rRNA study. The same study identified Endomicrobia (phylum:Elusimicrobia), which are predominant endosymbionts several protozoa in the termtie gut.
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1993 Bacteria are the chief agents of transformation of DOM and POM into bioavailable carbon through the microbial loop. This mechanism is particularly important in nutrient limited marine systems, where bacteria release nutrients from sinking detritus, allowing it to be recycled back to the photic zone. Little work has been applied to the function of the microbial loop in the San Francisco Estuary, but it may be that the role of bacteria is not critical for recycling nutrients in a eutrophic system. Rather, they may provide an alternative food chain through direct grazing by flagellates, rotifers and ciliates.
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In rare cases, infection has been caused by nasal or sinus rinsing with contaminated water in a nasal rinsing device such as a neti pot. N. fowleri normally eat bacteria, but during human infections, the trophozoites consume astrocytes and neurons. The reason why N. fowleri prefers to pass across the cribriform plate has remained unknown, but the neurotransmitter acetylcholine has been suggested to act as a stimulus, as a structural homolog of animal CHRM1 has been shown to be present in Naegleria and Acanthamoeba. It takes one to nine days (average five) for symptoms to appear after nasal exposure to N. fowleri flagellates.
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Euglenids (euglenoids, or euglenophytes, formally Euglenida/Euglenoida, ICZN, or Euglenophyceae, ICBN) are one of the best-known groups of flagellates, which are excavate eukaryotes of the phylum Euglenophyta and their cell structure is typical of that group. They are commonly found in freshwater, especially when it is rich in organic materials, with a few marine and endosymbiotic members. Many euglenids feed by phagocytosis, or strictly by diffusion. A monophyletic group consisting of the mixotrophic Rapaza viridis (1 species) and the two groups Eutreptiales (24 species) and Euglenales (983 species) have chloroplasts and produce their own food through photosynthesis.
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Most higher termites, especially in the family Termitidae, can produce their own cellulase enzymes, but they rely primarily upon the bacteria. The flagellates have been lost in Termitidae. Researches have found species of spirochetes living in termite guts capable of fixing atmospheric nitrogen to a form usable by the insect. Scientists' understanding of the relationship between the termite digestive tract and the microbial endosymbionts is still rudimentary; what is true in all termite species, however, is that the workers feed the other members of the colony with substances derived from the digestion of plant material, either from the mouth or anus.
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Biologists such as Margulis strongly advocate the use of the name, because of the apparent structural and functional differences between the cilia and flagella of prokaryotic and eukaryotic cells. They argue that the name flagella should be restricted only to prokaryotic organelles, such as bacterial flagella and spirochaete axial filaments. However, the term is not generally endorsed by most biologists because it is argued that the original purpose of the name does not sufficiently differentiate the cilia and flagella of eukaryotic from those of prokaryotic cells. For example, the early concept was the trivial homology of flagella of flagellates and pseudopodia of rhizopods.
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Depending upon the composition and timing of delivery, iron infusions could preferentially favor certain species and alter surface ecosystems to unknown effect. Population explosions of jellyfish, which disturb the food chain impacting whale populations or fisheries, are unlikely as iron fertilization experiments are conducted in high-nutrient, low-chlorophyll waters that favor the growth of larger diatoms over small flagellates. This has been shown to lead to increased abundance of fish and whales over jellyfish. A 2010 study showed that iron enrichment stimulates toxic diatom production in high-nitrate, low-chlorophyll areas which, the authors argue, raises "serious concerns over the net benefit and sustainability of large-scale iron fertilizations".
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Earthworms migrate only a limited distance annually on their own, and the spread of invasive worms is increased rapidly by anglers and from worms or their cocoons in the dirt on vehicle tires or footwear. Marine annelids may account for over one-third of bottom-dwelling animal species around coral reefs and in tidal zones. Burrowing species increase the penetration of water and oxygen into the sea-floor sediment, which encourages the growth of populations of aerobic bacteria and small animals alongside their burrows. Although blood-sucking leeches do little direct harm to their victims, some transmit flagellates that can be very dangerous to their hosts.
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Trophallaxis was used in the past to support theories on the origin of sociality in insects. The Swiss psychologist and entomologist Auguste Forel also believed that food sharing was key to ant society and he used an illustration of it as the frontispiece for his book The Social World of the Ants Compared with that of Man. Proctodeal trophallaxis allowed termites to transfer cellulolytic flagellates that made the digestion of wood possible and efficient. Besides sociality, trophallaxis has evolved within many species as a method of nourishment for adults and/ or juveniles, kin survival, transfer of symbionts, transfer of immunity, colony recognition and foraging communication.
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Mastigamoeba was described as a genus of species characterized by an ameboid body with a hyaline based cytoplasm and a flagellum. Due to its similarities to genera such as Mastigella and Mastigina, the genus Mastigamoeba was specified in 1891 to only include organisms with the following features: amoeboid flagellates with hyaline based cytoplasm, a direct connection between the flagellum and the nucleus, lateral pseudopods, and nucleus with an elongated shape. Throughout the 20th century, hundreds of species were described under the genus Mastigamoeba based on external morphological characteristics alone. However, recent discoveries regarding life cycles have shown that a single organism takes on many morphologies throughout its life cycle, putting the number of described species into question.
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Since superoxide is produced through the auto-oxidation of an electron acceptor in photosystem I during photosynthesis, one would expect a positive relationship between light levels and algal ROS production. This is indeed what has been shown: in the diatom Thallasia weissflogii, an increase in light intensity caused an increase in the production of both superoxide and hydrogen peroxide. Similarly, in the flagellates Chattonella marina, Prorocentrum minimum, and Cochlodinium polykrikoides, decreases in light levels resulted in decreases in superoxide production, with higher levels produced during the day. However, because many studies have found ROS production to be relatively high even in the dark, metabolic pathways other than photosynthesis are likely more important for production.
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In marine environments, HABs are mostly caused by dinoflagellates,Stewart I and Falconer IR (2008) "Cyanobacteria and cyanobacterial toxins" Pages 271–296 in Oceans and human health: risks and remedies from the seas, Eds: Walsh PJ, Smith SL and Fleming LE. Academic Press, . though species of other algae taxa can also cause HABs (diatoms, flagellates, haptophytes and raphidophytes).Moestrup Ø, Akselman R, Cronberg G, Elbraechter M, Fraga S, Halim Y, Hansen G, Hoppenrath M, Larsen J, Lundholm N, Nguyen LN and Zingone A. "IOC-UNESCO Taxonomic Reference List of Harmful Micro Algae (HABs)" Accessed 21 January 2011. Marine dinoflagellate species are often toxic, but freshwater species are not known to be toxic.
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Moreover, Opus Dei encourages its lay members to avoid practices that are perceived as fundamentalist to the outside world. The term personal prelature does not refer to a special relationship to the Pope; it means an institution in which the jurisdiction of the prelate is not linked to a territory but over persons, wherever they be. Silas, the murderous "Opus Dei monk", uses a cilice and flagellates himself. Some members of Opus Dei do practice voluntary mortification of the flesh, which has been a Christian tradition since at least St. Anthony in the third century, and it has also been practiced by Mother Teresa, Padre Pio, the child visionaries of Our Lady of Fatima, and slain archbishop Óscar Romero.
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Schematic drawing of Cafeteria roenbergensis (a bicosoecid) with two heterokont flagella: an anterior straminipilous (with tripartite mastigonemes) and a posterior smooth Many heterokonts are unicellular flagellates, and most others produce flagellated cells at some point in their lifecycles, for instance as gametes or zoospores. The name heterokont refers to the characteristic form of these cells, which typically have two unequal flagella. The anterior straminipilous flagellum is covered with one or two rows of lateral bristles or mastigonemes, which are tripartite (with three regions each), while the posterior flagellum is whiplike, smooth, and usually shorter, or sometimes reduced to a basal body. The flagella are inserted subapically or laterally, and are usually supported by four microtubule roots in a distinctive pattern.
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The relationship between opalines and other protists has been a subject of great controversy since the late 19th century, and is not completely resolved at present. Initially, microscopists believed that the thousands of rhythmically beating hair-like structures which cover their surface were cilia, and they placed the opalines in Ciliophora. In the early 20th century other aspects of opaline biology clearly differentiated them from the ciliates and they were placed in Sarcomastigophora, with the amoebae and flagellates. In the 1980s, detailed ultrastructural studies of Opalina ranarum revealed that they share many features with the heterokonts of the family Proteromonadidae. A new order—Slopalinida Patterson 1985—was proposed to include the members of the families Proteromonadidae Grassé 1952 and Opalinidae Claus 1874.
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Colponema is a single-celled predator that has been found in lakes, soil, reservoirs, marine sediment, and sewage waters. It is an obligate eukaryovore, meaning that it can only feed on other eukaryotes such as bodonids and does not tend to eat larger prey or bacteria. Their primary role in ecosystems is controlling the numbers of smaller flagellates. It is likely that larger eukaryotes and small animals are its primary predators, but the details of Colponema’s ecological role have yet to be characterized because it is relatively rare and difficult to culture. The genus’ scarcity further supports its position as a predator in the microbial food chain; predators are often present in smaller numbers because large amounts of prey are needed to sustain their population.
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Originally shown at the 2001 Venice Biennial, it's a stationary panorama in which several grotesque characters – again played by Ms. Rose – perform on a long altarlike tabletop. A schoolmarmish hostess comes and goes; a smiling blond nymphet in dead-white makeup flagellates herself; a woman in an 18th-century wig spasmodically spoons out chocolate cake; a black, nude woman is put on display and eventually hanged. Ms. Rose, who is based in South Africa, has tackled ideas of gender and race in interesting, sometimes audacious ways over the last few years. On the evidence of this show, her forms are rapidly growing more sophisticated, her images sharper, her thinking more complex – all of which bodes very well for the future of an artist still only in her 20s.
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