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Paratrimastix
''Paratrimastix'' is a genus of free-living freshwater anaerobic excavate protists from the group 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. ...a, that was segregated from the genus '' Trimastix'' in 2015. The best studied species is '' Paratrimastix pyriformis''. References {{Taxonbar, from=Q123753322 Metamonads Metamonad genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paratrimastix Pyriformis
''Paratrimastix pyriformis'' is a species of free-living (non-parasitic) anaerobic freshwater bacteriovorous flagellated protists formerly known as '' Trimastix pyriformis'' and '' Tetramitus pyriformis''. History of knowledge This species was first described by G. A. Klebs in 1892 as '' Tetramitus pyriformis''. Under this name, it has been frequently discussed in the context of sewage, sewage treatment, and water quality during the 20th century. It was also observed on Elephant Island, South Shetland Islands. More than 100 years after its description, in 1999, it was transferred to the genus '' Trimastix'' based on its morphology. The first ultrastructural study using transmission electron microscopy was published the same year, which reported a discovery of hydrogenosome-like organelles in the species. A molecular phylogenetic study based on small-subunit ribosomal RNA placed the genus '' Trimastix'' (then including ''P. pyriformis'') as sister to the oxymonad Pyrsonympha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preaxostyla
Anaeromonadea, also known as Preaxostyla, is a class of excavate protists, comprising the oxymonads, '' Trimastix'', and '' Paratrimastix''. This group is studied as a model system for reductive evolution of mitochondria, because it includes both organisms with anaerobic mitochondrion-like organelles ('' Trimastix'' and '' Paratrimastix''), and those that have completely lost their mitochondria ( oxymonads ''Monocercomonoides'', ''Streblomastix A symbiotic eukaryote that lives in the hindgut of termites, ''Streblomastix'' is a protist associated with a community of ectosymbiotic bacteria. Motility ''Streblomastix'' moves by beating its anterior flagella. Morphology These protists ...'', and '' Blattamonas''). Phylogeny and Taxonomy Based on the work of Zhang et al. 2015. References External links Tree of Life: Preaxostyla Metamonads {{Excavata-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimastix
''Trimastix'' is a genus of excavate protists, the sole occupant of the order Trimastigida. ''Trimastix'' are bacterivorous, free living and anaerobic. It was first observed in 1881 by William Kent. There are few known species, and the genus's role in the ecosystem is largely unknown. However, it is known that they generally live in marine environments within the tissues of decaying organisms to maintain an anoxic environment.Brugerolle, G., & Patterson, D. (1997). Ultrastructure of Trimastix convexa Hollande, an amitochondriate anaerobic flagellate with a previously undescribed organization. European Journal of Protistology, 33(2), 121-130. Much interest in this group is related to its close association with other members of Preaxostyla. These organisms do not have classical mitochondria, and as such, much of the research involving these microbes is aimed at investigating the evolution of mitochondria. A freshwater flagellate of similar morphology used to be included in this ge ... [...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] |
Protist
A protist ( ) or protoctist is any eukaryotic organism that is not an animal, land plant, or fungus. Protists do not form a natural group, or clade, but are a paraphyletic grouping of all descendants of the last eukaryotic common ancestor excluding land plants, animals, and fungi. Protists were historically regarded as a separate taxonomic kingdom known as Protista or Protoctista. With the advent of phylogenetic analysis and electron microscopy studies, the use of Protista as a formal taxon was gradually abandoned. In modern classifications, protists are spread across several eukaryotic clades called supergroups, such as Archaeplastida ( photoautotrophs that includes land plants), SAR, Obazoa (which includes fungi and animals), Amoebozoa and " Excavata". Protists represent an extremely large genetic and ecological diversity in all environments, including extreme habitats. Their diversity, larger than for all other eukaryotes, has only been discovered in rece ... [...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] |
Metamonads
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 organism, anaerobic (many being aerotolerant anaerobes), and most members of the four groups listed above are symbiosis, symbiotes or parasitism, parasites of animals, as is the case with Giardia duodenalis, ''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 Parasitism, parasites. These flagellates are unusual in lacking aerobic mitochondrion, 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 mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
The eukaryotes ( ) constitute the Domain (biology), domain of Eukaryota or Eukarya, organisms whose Cell (biology), cells have a membrane-bound cell nucleus, nucleus. All animals, plants, Fungus, fungi, seaweeds, and many unicellular organisms are eukaryotes. They constitute a major group of Outline of life forms, life forms alongside the two groups of prokaryotes: the Bacteria and the Archaea. Eukaryotes represent a small minority of the number of organisms, but given their generally much larger size, their collective global biomass is much larger than that of prokaryotes. The eukaryotes emerged within the archaeal Kingdom (biology), kingdom Asgard (Archaea), Promethearchaeati and its sole phylum Promethearchaeota. This implies that there are only Two-domain system, two domains of life, Bacteria and Archaea, with eukaryotes incorporated among the Archaea. Eukaryotes first emerged during the Paleoproterozoic, likely as Flagellated cell, flagellated cells. The leading evolutiona ... [...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] |
Fresh Water
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salt (chemistry), salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mineral water, mineral-rich waters, such as chalybeate springs. Fresh water may encompass frozen water, frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/ice pellets, sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranea (geography), subterranean subterranean river, rivers and underground lake, lakes. Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of vascular plants and most insects, amphibians, reptiles, mammals and birds need fresh water to sur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaerobic Organism
An anaerobic organism or anaerobe is any organism that does not require oxygen, molecular oxygen for growth. It may react negatively or even die if free oxygen is present. In contrast, an aerobic organism (aerobe) is an organism that requires an oxygenated environment. Anaerobes may be unicellular (e.g. protozoans, bacteria) or multicellular. Most fungi are obligate aerobes, requiring oxygen to survive. However, some species, such as the Chytridiomycota that reside in the rumen of cattle, are obligate anaerobes; for these species, anaerobic respiration is used because oxygen will disrupt their metabolism or kill them. The sea floor is possibly one of the largest accumulation of anaerobic organisms on Earth, where microbes are primarily concentrated around Hydrothermal_vent, hydrothermal vents. These microbes produce energy in absence of sunlight or oxygen through a process called chemosynthesis, whereby inorganic compounds such as hydrogen gas, hydrogen sulfide or ferrous ions are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
