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Opisthokont
The opisthokonts () are a broad group of eukaryotes, including both the animal and fungus kingdoms. The opisthokonts, previously called the "Fungi/Metazoa group", are generally recognized as a clade. Opisthokonts together with Apusomonadida and Breviata comprise the larger clade Obazoa. Flagella and other characteristics A common characteristic of opisthokonts is that flagellate cells, such as the sperm of most animals and the spores of the chytrid fungi, propel themselves with a single ''posterior'' flagellum. It is this feature that gives the group its name. In contrast, flagellate cells in other eukaryote groups propel themselves with one or more ''anterior'' flagella. However, in some opisthokont groups, including most of the fungi, flagellate cells have been lost. Opisthokont characteristics include synthesis of extracellular chitin in exoskeleton, cyst/spore wall, or cell wall of filamentous growth and hyphae; the extracellular digestion of substrates with osmotrophic ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Obazoa
Obazoa (Brown et al., 2013) is a proposed sister clade of Amoebozoa (which together form Amorphea). Obazoa is composed of Breviatea, Apusomonadida and Opisthokonta. The term Obazoa is based on the OBA acronym for Opisthokonta, Breviatea, and Apusomonadida. Determining the placement of Breviatea and Apusomonadida and their properties is of interest for the development of the opisthokonts in which the main lineages of animals and fungi emerged. The relationships among opisthokonts, breviates and apusomonads are not conclusively resolved (as of 2018), though Breviatea is usually inferred to be the most basal of the three lineages. Ribosomal RNA phylogenies do not usually recover Obazoa as a clade (see for example:), probably reflecting their stemming from a very ancient common ancestor, and little phylogenetic signal Phylogenetic signal is an evolutionary and ecological term, that describes the tendency or the pattern of related biological species to resemble each other more tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''tru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleariida
Nucleariida is a group of amoebae with filose pseudopods, known mostly from soils and freshwater. They are distinguished from the superficially similar vampyrellids mainly by having mitochondria with discoid cristae, in the absence of superficial granules, and in the way they consume food. Classification Molecular studies indicate that nucleariids are closely related to fungi. and more distantly to the lineage that gave rise to choanoflagellates and metazoa opisthokonts, the group which includes animals, fungi. Some use a broad definition of Opisthokonta to include all of these organisms with flattened mitochondrial cristae. The genera '' Rabdiophrys'', '' Pinaciophora'', and '' Pompholyxophrys'', freshwater forms with hollow siliceous scales or spines, were included in Nucleariida by some. This was disputed by Smith and Chao who placed them in the Rhizaria. Their affinity with the nucleariids has been confirmed. Historically, nucleariids were included among the heliozoa a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Cavalier-Smith
Thomas (Tom) Cavalier-Smith, FRS, FRSC, NERC Professorial Fellow (21 October 1942 – 19 March 2021), was a professor of evolutionary biology in the Department of Zoology, at the University of Oxford. His research has led to discovery of a number of unicellular organisms (protists) and advocated for a variety of major taxonomic groups, such as the Chromista, Chromalveolata, Opisthokonta, Rhizaria, and Excavata. He was known for his systems of classification of all organisms. Life and career Cavalier-Smith was born on 21 October 1942 in London. His parents were Mary Maude (née Bratt) and Alan Hailes Spencer Cavalier Smith. He was educated at Norwich School, Gonville and Caius College, Cambridge (MA) and King's College London (PhD). He was under the supervision of Sir John Randall for his PhD thesis between 1964 and 1967; his thesis was entitled "''Organelle Development in'' Chlamydomonas reinhardii". From 1967 to 1969, Cavalier-Smith was a guest inves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesomycetozoea
The Mesomycetozoea (or DRIP clade, or Ichthyosporea) are a small group of Opisthokonta in Eukaryota (formerly protists), mostly parasites of fish and other animals. Significance They are not particularly distinctive morphologically, appearing in host tissues as enlarged spheres or ovals containing spores, and most were originally classified in various groups as fungi, protozoa, or colorless algae. However, they form a coherent group on molecular trees, closely related to both animals and fungi and so of interest to biologists studying their origins. In a 2008 study they emerge robustly as the sibling-group of the clade Filozoa, which includes the animals. Huldtgren et al., following x-ray tomography of microfossils of the Ediacaran Doushantuo Formation, has interpreted them as mesomycetozoan spore capsules. Terminology The name DRIP is an acronym for the first protozoa identified as members of the group, Cavalier-Smith later treated them as the class Ichthyosporea, since they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoospore
A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate themselves. Diversity Flagella types Zoospores may possess one or more distinct types of flagella - tinsel or "decorated", and whiplash, in various combinations. *Tinsellated (straminipilous) flagella have lateral filaments known as mastigonemes perpendicular to their main axis, which allow for more surface area, and disturbance of the medium, giving them the property of a rudder, that is, used for steering. *Whiplash flagella are straight, to power the zoospore through its medium. Also, the "default" zoospore only has the propelling, whiplash flagella. Both tinsel and whiplash flagella beat in a sinusoidal wave pattern, but when both are present, the tinsel beats in the opposite direction of the whiplash, to give two axes of control of motility. Morphological types In eukaryotes, the four main ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoospore
A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate themselves. Diversity Flagella types Zoospores may possess one or more distinct types of flagella - tinsel or "decorated", and whiplash, in various combinations. *Tinsellated (straminipilous) flagella have lateral filaments known as mastigonemes perpendicular to their main axis, which allow for more surface area, and disturbance of the medium, giving them the property of a rudder, that is, used for steering. *Whiplash flagella are straight, to power the zoospore through its medium. Also, the "default" zoospore only has the propelling, whiplash flagella. Both tinsel and whiplash flagella beat in a sinusoidal wave pattern, but when both are present, the tinsel beats in the opposite direction of the whiplash, to give two axes of control of motility. Morphological types In eukaryotes, the four main ... [...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, the term "flagellate" is included in other terms (such as " dinoflagellate" and " choanoflagellata") which 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 often support hairs, called mastigonemes, or contain rods. Their ultrastructure plays an important role in classifying eukaryotes. Among protoctists and micros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breviata
''Breviata anathema'' is a single-celled flagellate amoeboid eukaryote, previously studied under the name ''Mastigamoeba invertens''. The cell lacks mitochondria but has remnant mitochondrial genes, and possesses an organelle believed to be a modified anaerobic mitochondrion, similar to the mitosomes and hydrogenosomes found in other eukaryotes that live in low-oxygen environments. Early molecular data placed ''Breviata'' in the Amoebozoa, but without obvious affinity to known amoebozoan groups. More recently, phylogenomic analysis has shown that the class Breviatea is a sister group to the Opisthokonta and Apusomonadida. Together, these three groups form the clade Obazoa (the term Obazoa is based on an acronym of Opisthokonta, Breviatea, and Apusomonadida, plus ‘zóa’ (pertaining to ‘life’ in Greek)). Taxonomy * Class Breviatea ''Breviata anathema'' is a single-celled flagellate amoeboid eukaryote, previously studied under the name ''Mastigamoeba invertens''. The cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apusomonadida
The Apusomonadida are a group of protozoan zooflagellates that glide on surfaces, and mostly consume prokaryotes. They are of particular evolutionary interest because they appear to be the sister group to the Opisthokonts, the clade that includes both animals and fungi. Together with the Breviatea, these form the Obazoa clade. Taxonomy * Class Apusomonadea Tedersoo 2017 ** Order Apusomonadida Karpov & Mylnikov 1989 hecomonadales Lee 1989*** Family Apusomonadidae Karpov & Mylnikov 1989 **** Genus '' Amastigomonas'' de Saedeleer 1931 ***** Species '' A. caudata'' Mylnikov 1989 'Amastigomonas borokensis'' Hamar 1979***** Species '' A. debruynei'' de Saedeleer 1931 ***** Species '' A. marisrubri'' Mylnikov & Mylnikov 2012 **** Genus ''Multimonas'' Cavalier-Smith 2010 ***** Species '' M. koreensis'' Heiss et al. 2015 ***** Species '' M. marina'' (Mylnikov 1989) Cavalier-Smith 2010 'Cercomonas marina'' Mylnikov 1989; ''Amastigomonas marina'' (Mylnikov 1989) Mylnikov 1999***** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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