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Malawimonas Californiana
''Malawimonas'' is genus of unicellular, heterotrophic flagellates with uncertain phylogenetic affinities. They have variably being assigned to Excavata and Loukozoa. Recent studies suggest they may be closely related to the Podiata. Discovery history In 1993, Charles J O’ Kelly studied the jakobid groups flagellates and implications for the early diversification of eukaryotes and recognized that ''Jakoba, Reclimonas,'' and ''Histonia'', often referred to as “core jakobids” were morphologically somewhat similar. Interestingly, they included an unnamed and undescribed free-swimming, flagellate, and also groove- bearing cell. During the early study, these cells were thought to be a member from ''Jakoba'' due to the external morphology features that resembles ''Jakoba libera'' in terms of lack of cell covering, sessile trophic stages, swimming in a similar manner and sharing the tendency for the anterior flagellum to form a “crook. However, later discovery found that this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour, or ecological niche. In addition, palaeontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomen". The first part of a binomen is the name of a genus to which the species belongs. The second part is called the specific name (zoology), specific name or the specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterotroph
A heterotroph (; ) is an organism that cannot produce its own food, instead taking nutrition from other sources of organic carbon, mainly plant or animal matter. In the food chain, heterotrophs are primary, secondary and tertiary consumers, but not producers. Living organisms that are heterotrophic include all animals and fungi, some bacteria and protists, and many parasitic plants. The term heterotroph arose in microbiology in 1946 as part of a classification of microorganisms based on their type of Primary nutritional groups, nutrition. The term is now used in many fields, such as ecology, in describing the food chain. Heterotrophs occupy the second and third trophic levels of the food chain while autotrophs occupy the first trophic level. Heterotrophs may be subdivided according to their energy source. If the heterotroph uses chemical energy, it is a chemotroph, chemoheterotroph (e.g., humans and mushrooms). If it uses light for energy, then it is a photoheterotroph (e.g., gre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagellate
A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word ''flagellate'' also describes a particular construction (or level of organization) characteristic of many prokaryotes and eukaryotes and their means of motion. The term presently does not imply any specific relationship or classification of the organisms that possess flagella. However, several derivations of the term "flagellate" (such as " dinoflagellate" and " choanoflagellate") are more formally characterized. Form and behavior Flagella in eukaryotes 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 role in classifying eukaryotes. Among protoctists and microscopic animals, a flagellate is an organism with one or more flagella. Some cells in other animals may be flage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Excavata
Excavata is an obsolete, extensive and diverse paraphyletic group of unicellular Eukaryota. The group was first suggested by Simpson and Patterson in 1999 and the name latinized and assigned a rank by Thomas Cavalier-Smith in 2002. It contains a variety of free-living and symbiotic protists, and includes some important parasites of humans such as ''Giardia'' and '' Trichomonas''. Excavates were formerly considered to be included in the now- obsolete Protista kingdom. They were distinguished from other lineages based on electron-microscopic information about how the cells are arranged (they have a distinctive ultrastructural identity). They are considered to be a basal flagellate lineage. On the basis of phylogenomic analyses, the group was shown to contain three widely separated eukaryote groups, the discobids, metamonads, and malawimonads. A current view of the composition of the excavates is given below, indicating that the group is paraphyletic. Except for some Eugleno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loukozoa
Loukozoa (From Greek ''loukos'': groove) is a proposed taxon used in some classifications of eukaryotes, consisting of the Metamonada and Malawimonadea. Ancyromonads are closely related to this group, as sister of the entire group, or as sister of the Metamonada. Amorphea may have emerged in this grouping, specifically as sister of the Malawimonads. Originally, Loukozoa included Anaeromonadea and Jakobea. In 2013, it consisted of three subphyla: Eolouka ( Tsukubea and Jakobea), Metamonada and Neolouka ('' Malawimonas''). In 2018, Cavalier-Smith has removed Eolouka from Loukozoa, placing it instead in Discoba Excavata is an obsolete, extensive and diverse Paraphyly, paraphyletic group of unicellular Eukaryote, Eukaryota. The group was first suggested by Simpson and Patterson in 1999 and the name latinized and assigned a rank by Thomas Cavalier-Smit .... With the root of the Eukaryota likely close to or in Loukozoa or Discoba, these groupings are studied to give unique i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podiata
Podiates (Cavalier-Smith, 2012, excl. Ancyromonadida) are a proposed clade containing the Amorphea (incl. Opisthokonta, Amoebozoa, apusomonads and breviates) and the organisms now assigned to the clade CRuMs. Ancyromonadida does not appear to have emerged in this grouping. Sarcomastigota (Cavalier-Smith, 1983) is a proposed subkingdom (currently shown to be paraphyletic) that includes all the podiates that are ''not'' animals or fungi. Sulcozoa (Cavalier-Smith, 2012) is a proposed phylum (currently shown to be paraphyletic) within Sarcomastigota that does not include the phyla Amoebozoa (clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...) and Choanozoa (paraphyletic), i.e. it includes the proposed subphyla Apusozoa and Varisulca.. References {{Taxonbar, from=Q ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Nyasa
Lake Malawi, also known as Lake Nyasa in Tanzania and Lago Niassa in Mozambique, () is an African Great Lake and the southernmost lake in the East African Rift system, located between Malawi, Mozambique and Tanzania. It is the fourth largest freshwater lake in the world by volume, the ninth largest lake in the world by area and the third largest and second deepest lake in Africa. Lake Malawi is home to more species of fish than any other lake in the world, including at least 700 species of cichlids.Turner, Seehausen, Knight, Allender, and Robinson (2001). "How many species of cichlid fishes are there in African lakes?" ''Molecular Ecology'' 10: 793–806. The Mozambique portion of the lake was officially declared a reserve by the Government of Mozambique on June 10, 2011,WWF (10 June 2011)"Mozambique’s Lake Niassa declared reserve and Ramsar site"Retrieved 17 July 2014. while in Malawi a portion of the lake is included in Lake Malawi National Park. Lake Malawi is a merom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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7 (seven) is the natural number following 6 and preceding 8. It is the only prime number preceding a cube. As an early prime number in the series of positive integers, the number seven has symbolic associations in religion, mythology, superstition and philosophy. The seven classical planets resulted in seven being the number of days in a week. 7 is often considered lucky in Western culture and is often seen as highly symbolic. Evolution of the Arabic digit For early Brahmi numerals, 7 was written more or less in one stroke as a curve that looks like an uppercase vertically inverted (ᒉ). The western Arab peoples' main contribution was to make the longer line diagonal rather than straight, though they showed some tendencies to making the digit more rectilinear. The eastern Arab peoples developed the digit from a form that looked something like 6 to one that looked like an uppercase V. Both modern Arab forms influenced the European form, a two-stroke form consisting of a ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpediemonas
''Carpediemonas'' is genus of Metamonada, and belongs to the group Excavata. This organism is a unicellular flagellated eukaryote that was first discovered in substrate samples from the Great Barrier Reef. ''Carpediemonas'' can be found in anaerobic intertidal sediment, where it feeds on bacteria. A feature of this species is the presence of a feeding groove, a characteristic of the excavates. Like most other metamonads, ''Carpediemonas'' does not rely on an aerobic mitochondrion to produce energy. Instead, it contains hydrogenosomes that are used to produce ATP. This organism has two flagella: a posterior one used for feeding on the substrate, and an anterior one that moves in a slower sweeping motion. ''Carpediemonas'' is assigned to the fornicates, where similar ''Carpediemonas''-like organisms are used in researching the evolution within excavates. Although ''Carpediemonas'' is a member of the metamonads, it is unusual in the sense that it is free-living and has three basal bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamonad
The metamonads are a large group of flagellate amitochondriate microscopic eukaryotes. They include the retortamonads, diplomonads, parabasalids, oxymonads, and a range of more poorly studied taxa, most of which are free-living flagellates. All metamonads are anaerobic (many being aerotolerant anaerobes), and most members of the four groups listed above are symbiotes or parasites of animals, as is the case with ''Giardia lamblia'' which causes diarrhea in mammals. Characteristics 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 aerobic mitochondria. Originally they were considered among the most primitive eukaryotes, diverging from the others before mitochondria appeared. However, they are now known to have lost aerobic mitochondria secondarily, and retain both organelles and nuclear genes derived ultimate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplomonad
The diplomonads (Greek for "two units") are a group of flagellates, most of which are parasitic. They include ''Giardia duodenalis'', which causes giardiasis in humans. They are placed among the metamonads, and appear to be particularly close relatives of the retortamonads. Morphology Most diplomonads are double cells: they have two nuclei, each with four associated flagella, arranged symmetrically about the body's main axis. Like the retortamonads, they lack both mitochondria and Golgi apparatuses. However, they are now known to possess modified mitochondria, in the case of ''G. duodenalis'', called mitosomes. These are not used in ATP synthesis the way mitochondria are, but are involved in the maturation of iron-sulfur proteins. Possible sexual reproduction in ''Giardia'' The common intestinal parasite ''Giardia duodenalis'' (synonyms ''Giardia lamblia'', ''G. intestinalis'') was once considered to be a descendant of a protist lineage that predated the emergence of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reclinomonas
''Reclinomonas'' is a monotypic genus of jakobid eukaryotes containing the single species ''Reclinomonas americana''.Simpson, A. 2008''Reclinomonas'' Flavin & Nerad 1993. ''Reclinomonas americana'' Flavin & Nerad 1993.Version 05. The Tree of Life Web Project. This organism is a single cell up to 12 micrometers wide. It has two flagella. The cell is in a cup-like lorica which has a stem that attaches to a surface. When the cell reproduces, by undergoing binary fission, one of the two newly split cells produces a new lorica for itself. This protozoan can be found in freshwater. This species was the first jakobid to have its mitochondrial genome sequenced. It contains 97 genes, 62 of them code for proteins.Berg, J. M., et al. Biochemistry.' Edition 6. Macmillan. 2010. pg. 505. Other jakobids have been sequenced since, and the data were similar. It has been described as a member of the Excavata Excavata is an obsolete, extensive and diverse paraphyletic group of unicellular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
