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Kinetoplastea
Kinetoplastida (or Kinetoplastea, as a class) is a group of flagellated protists belonging to the phylum Euglenozoa, and characterised by the presence of a distinctive organelle called the kinetoplast (hence the name), a granule containing a large mass of DNA. The group includes a number of parasites responsible for serious diseases in humans and other animals, as well as various forms found in soil and aquatic environments. The organisms are commonly referred to as "kinetoplastids" or "kinetoplasts". The kinetoplastids were first defined by Bronislaw M. Honigberg in 1963 as the members of the flagellated protozoans. They are traditionally divided into the biflagellate Bodonidae and uniflagellate Trypanosomatidae; the former appears to be paraphyletic to the latter. One family of kinetoplastids, the trypanosomatids, is notable as it includes several genera which are exclusively parasitic. '' Bodo'' is a typical genus within kinetoplastida, which also includes various common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euglenozoa
Euglenozoa are a large group of flagellate Discoba. They include a variety of common free-living species, as well as a few important parasites, some of which infect humans. Euglenozoa are represented by four major groups, ''i.e.,'' Kinetoplastea, Diplonemea, Euglenida, and Symbiontida. Euglenozoa are unicellular, mostly around in size, although some euglenids get up to long. Structure Most euglenozoa have two flagella, which are inserted parallel to one another in an apical or subapical pocket. In some these are associated with a cytostome or mouth, used to ingest bacteria or other small organisms. This is supported by one of three sets of microtubules that arise from the flagellar bases; the other two support the dorsal and ventral surfaces of the cell. Some other euglenozoa feed through absorption, and many euglenids possess chloroplasts, the only eukaryotes outside Diaphoretickes to do so without performing kleptoplasty, and so obtain energy through photosynthesis. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trypanosoma Cruzi
''Trypanosoma cruzi'' is a species of parasitic euglenoids. Among the protozoa, the trypanosomes characteristically bore tissue in another organism and feed on blood (primarily) and also lymph. This behaviour causes disease or the likelihood of disease that varies with the organism: Chagas disease in humans, dourine and surra in horses, and a brucellosis-like disease in cattle. Parasites need a host body and the haematophagous insect triatomine (descriptions "assassin bug", "cone-nose bug", and "kissing bug") is the major vector in accord with a mechanism of infection. The triatomine likes the nests of vertebrate animals for shelter, where it bites and sucks blood for food. Individual triatomines infected with protozoa from other contact with animals transmit trypanosomes when the triatomine deposits its faeces on the host's skin surface while blood feeding. Penetration of the infected faeces is further facilitated by the scratching of the bite area by the human or animal h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasite
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of life. The entomologist E. O. Wilson characterised parasites' way of feeding as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as Armillaria mellea, honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the Orobanchaceae, broomrapes. There are six major parasitic Behavioral ecology#Evolutionarily stable strategy, strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), wikt:trophic, trophicallytransmitted parasitism (by being eaten), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lynn Margulis
Lynn Margulis (born Lynn Petra Alexander; March 5, 1938 – November 22, 2011) was an American evolutionary biologist, and was the primary modern proponent for the significance of symbiogenesis, symbiosis in evolution. In particular, Margulis transformed and fundamentally framed current understanding of the evolution of Eukaryote, cells with nuclei by proposing it to have been the result of symbiotic mergers of bacteria. Margulis was also the co-developer of the Gaia hypothesis with the British chemist James Lovelock, proposing that the Earth functions as a single self-regulating system, and was the principal defender and promulgator of the Five kingdoms, five kingdom classification of Robert Whittaker (ecologist), Robert Whittaker. Throughout her career, Margulis' work could arouse intense objections, and her formative paper, "On the Origin of Mitosing Cells", appeared in 1967 after being rejected by about fifteen journals. Still a junior faculty member at Boston University at t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. For some groups of organisms, their orders may follow consist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxon
In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion, especially in the context of rank-based (" Linnaean") nomenclature (much less so under phylogenetic nomenclature). If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were presumably set forth in prehistoric times by hunter-gatherers, as suggested by the fairly sophisticated folk taxonomies. Much later, Aristotle, and later st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leishmania
''Leishmania'' () is a genus of parasitic protozoans, single-celled eukaryotic organisms of the trypanosomatid group that are responsible for the disease leishmaniasis. The parasites are transmitted by sandflies of the genus '' Phlebotomus'' in the Old World, and of the genus '' Lutzomyia'' in the New World. There are 53 species and about 20 of them are responsible for human infections. They are transmitted by around 100 species of sandflies. The primary hosts are vertebrates. They commonly infect hyraxes, canids, rodents, and humans. History Members of an ancient genus of ''Leishmania''-like parasites, '' Paleoleishmania'', have been detected in fossilized sand flies dating back to the early Cretaceous period. The first written reference to the conspicuous symptoms of cutaneous leishmaniasis surfaced in the Paleotropics within oriental texts dating back to the 7th century BC (allegedly transcribed from sources several hundred years older, between 1500 and 2000 BC). D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptobia
''Cryptobia'' is a genus of kinetoplastids. Several species are known for being fish pathogens. They can be found in other animals, as well. The name ''Trypanoplasma'' is occasionally used for some of these.Woo, P. T. K. (2003)''Cryptobia'' (''Trypanoplasma'') ''salmositica'' and salmonid cryptobiosis.''Journal of Fish Diseases'' 26(11-12) 627–46. Biology There are 52 species of ''Cryptobia'' known from fish. 40 of these live in the blood, 7 in the gut, and 5 on the body surface. Examples include: *'' Cryptobia branchialis'', an ectoparasite that lives on the skin or gills. It can deform the skin and cause anorexia and death. *'' Cryptobia iubilans'', an endoparasite that lives in the intestines and causes granulomatous inflammation of the abdominal organs, resulting in weight loss and death. *'' Cryptobia salmositica'', '' C. borreli'', and '' C. bullocki'', blood parasites that lead to anaemia and lesions in the haematopoietic tissues. Some ''Cryptobia'' parasitize other a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit the air, soil, water, Hot spring, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria play a vital role in many stages of the nutrient cycle by recycling nutrients and the nitrogen fixation, fixation of nitrogen from the Earth's atmosphere, atmosphere. The nutrient cycle includes the decomposition of cadaver, dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bodo (genus)
''Bodo'' () is a genus of microscopic kinetoplastids, flagellate excavates first described in 1831 by Christian Gottfried Ehrenberg. The genus is small, as it has recently been redefined to include only four species. ''Bodo'' includes free-living, phagotrophic organisms that can be found in many marine and freshwater environments as well as some terrestrial environments. Being phagotrophic, ''Bodo'' feeds on bacteria and other microorganisms that it finds while swimming through its water-based habitats. The swimming-like movement is facilitated by the two unequal flagella that ''Bodo'' possesses which arise from an anteriorly located flagellar pocket. ''Bodo'' is roughly bean-shaped and is often missed in samples from water or terrestrial environments due to its small size. History The genus was originally described in 1831 by Christian Gottfried Ehrenberg as having an ovoid body, a very short tail, transparent and able to show the colour of the food that it ingests. Ehrenberg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
