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Amoebozoa
Amoebozoa is a major taxonomic group containing about 2,400 described species of amoeboid protists, often possessing blunt, fingerlike, lobose pseudopods and tubular mitochondrial cristae. In traditional and currently no longer supported classification schemes, Amoebozoa is ranked as a phylum within either the kingdom Protista or the kingdom Protozoa. In the classification favored by the International Society of Protistologists, it is retained as an unranked " supergroup" within Eukaryota. Molecular genetic analysis supports Amoebozoa as a monophyletic clade. Modern studies of eukaryotic phylogenetic trees identify it as the sister group to Opisthokonta, another major clade which contains both fungi and animals as well as several other clades comprising some 300 species of unicellular eukaryotes. Amoebozoa and Opisthokonta are sometimes grouped together in a high-level taxon, variously named Unikonta, Amorphea or Opimoda. Amoebozoa includes many of the best-known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconosa
Amoebozoa is a major taxonomic group containing about 2,400 described species of amoeboid protists, often possessing blunt, fingerlike, lobose pseudopods and tubular mitochondrial cristae. In traditional and currently no longer supported classification schemes, Amoebozoa is ranked as a phylum within either the kingdom Protista or the kingdom Protozoa. In the classification favored by the International Society of Protistologists, it is retained as an unranked "supergroup" within Eukaryota. Molecular genetic analysis supports Amoebozoa as a monophyletic clade. Modern studies of eukaryotic phylogenetic trees identify it as the sister group to Opisthokonta, another major clade which contains both fungi and animals as well as several other clades comprising some 300 species of unicellular eukaryotes. Amoebozoa and Opisthokonta are sometimes grouped together in a high-level taxon, variously named Unikonta, Amorphea or Opimoda. Amoebozoa includes many of the best-known amoeboid organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutosa
Amoebozoa is a major taxonomic group containing about 2,400 described species of amoeboid protists, often possessing blunt, fingerlike, lobose pseudopods and tubular mitochondrial cristae. In traditional and currently no longer supported classification schemes, Amoebozoa is ranked as a phylum within either the kingdom Protista or the kingdom Protozoa. In the classification favored by the International Society of Protistologists, it is retained as an unranked " supergroup" within Eukaryota. Molecular genetic analysis supports Amoebozoa as a monophyletic clade. Modern studies of eukaryotic phylogenetic trees identify it as the sister group to Opisthokonta, another major clade which contains both fungi and animals as well as several other clades comprising some 300 species of unicellular eukaryotes. Amoebozoa and Opisthokonta are sometimes grouped together in a high-level taxon, variously named Unikonta, Amorphea or Opimoda. Amoebozoa includes many of the best-known amoeboid org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discosea
Discosea is a class of Amoebozoa, consisting of naked amoebae with a flattened, discoid body shape. Members of the group do not produce tubular or subcylindrical pseudopodia, like amoebae of the class Tubulinea. When a discosean is in motion, a transparent layer called ''hyaloplasm'' forms at the leading edge of the cell (see lamelliopodium). In some discoseans, short "subpseudopodia" may be extended from this hyaloplasm, but the granular contents of the cell do not flow into these, as in true pseudopodia. Discosean amoebae lack hard shells, but some, like '' Cochliopodium'' and '' Korotnevella'' secrete intricate organic scales which may cover the upper (dorsal) surface of the cell. No species have flagella or flagellated stages of life. The composition of Discosea is similar to that of the class Flabellinea, proposed by Alexey Smirnov and his collaborators in 2005. However, Discosea is a more comprehensive taxon, including several groups not included in Flabellinea. In 201 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centramoebia
Discosea is a class of Amoebozoa, consisting of naked amoebae with a flattened, discoid body shape. Members of the group do not produce tubular or subcylindrical pseudopodia, like amoebae of the class Tubulinea. When a discosean is in motion, a transparent layer called ''hyaloplasm'' forms at the leading edge of the cell (see lamelliopodium). In some discoseans, short "subpseudopodia" may be extended from this hyaloplasm, but the granular contents of the cell do not flow into these, as in true pseudopodia. Discosean amoebae lack hard shells, but some, like '' Cochliopodium'' and '' Korotnevella'' secrete intricate organic scales which may cover the upper (dorsal) surface of the cell. No species have flagella or flagellated stages of life. The composition of Discosea is similar to that of the class Flabellinea, proposed by Alexey Smirnov and his collaborators in 2005. However, Discosea is a more comprehensive taxon, including several groups not included in Flabellinea. In 2011, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutosea
Lobosa is a taxonomic group of amoebae in the phylum Amoebozoa. Most lobosans possess broad, bluntly rounded pseudopods, although one genus in the group, the recently discovered ''Sapocribrum,'' has slender and threadlike (filose) pseudopodia. In current classification schemes, Lobosa is a subphylum, composed mainly of amoebae that have lobose pseudopods but lack cilia or flagella. Characteristics The group was originally proposed in 1861 by William B. Carpenter, who created it as a taxonomic order containing the single family Amoebina. Carpenter's Lobosa consisted of amoeboid organisms whose endoplasm (endosarc) flows into lobe-like "pseudopodian prolongations." This type of pseudopod, which was understood to be typical of the genus Amoeba "and its allies," differed from the filose (thread-like) or reticulose (netlike) pseudopods of the Foraminifera. The name Lobosa was chosen for these amoebae "as expressing the lobe-like character of their pseudopodial extensions". As curren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lobosa
Lobosa is a taxonomic group of amoebae in the phylum Amoebozoa. Most lobosans possess broad, bluntly rounded pseudopods, although one genus in the group, the recently discovered ''Sapocribrum,'' has slender and threadlike (filose) pseudopodia. In current classification schemes, Lobosa is a subphylum, composed mainly of amoebae that have lobose pseudopods but lack cilia or flagella. Characteristics The group was originally proposed in 1861 by William B. Carpenter, who created it as a taxonomic order containing the single family Amoebina. Carpenter's Lobosa consisted of amoeboid organisms whose endoplasm (endosarc) flows into lobe-like "pseudopodian prolongations." This type of pseudopod, which was understood to be typical of the genus Amoeba "and its allies," differed from the filose (thread-like) or reticulose (netlike) pseudopods of the Foraminifera. The name Lobosa was chosen for these amoebae "as expressing the lobe-like character of their pseudopodial extensions". As curr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amoeba
An amoeba (; less commonly spelled ameba or amœba; plural ''am(o)ebas'' or ''am(o)ebae'' ), often called an amoeboid, is a type of cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudopods. Amoebae do not form a single taxonomic group; instead, they are found in every major lineage of eukaryotic organisms. Amoeboid cells occur not only among the protozoa, but also in fungi, algae, and animals. Microbiologists often use the terms "amoeboid" and "amoeba" interchangeably for any organism that exhibits amoeboid movement. In older classification systems, most amoebae were placed in the class or subphylum Sarcodina, a grouping of single-celled organisms that possess pseudopods or move by protoplasmic flow. However, molecular phylogenetic studies have shown that Sarcodina is not a monophyletic group whose members share common descent. Consequently, amoeboid organisms are no longer classified together in one group.Jan Pawl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flabellinia
The Flabellinia are a subclass of Amoebozoa. During locomotion the cells are flattened and have a clear layer called ''hyaloplasm'' along the front margin. Some form slender subpseudopodia projecting outward from the hyaloplasm, but the cell mass does not flow into these as in true pseudopodia, and advances without a definite central axis as in the Tubulinea. They also lack distinctive features like shells and flagella A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have fro ..., and are united mainly by evidence from molecular trees. The group was originally created by Alexey Smirnov and his coauthors as the class Flabellinea, which was similar in composition to the group Discosea, proposed by Cavalier-Smith ''et al.'' (2004). In 2011, Smirnov accepted Discosea as a class and reduced Fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tubulinea
The Tubulinea are a major grouping of Amoebozoa, including most of the more familiar amoebae genera like ''Amoeba'', '' Arcella'', ''Difflugia'' and '' Hartmannella''. Characteristics During locomotion most Tubulinea have a roughly cylindrical form or produce numerous cylindrical pseudopods. Each cylinder advances by a single central stream of cytoplasm, granular in appearance, and has no subpseudopodia. This distinguishes them from other amoeboid groups, although in some members this is not the normal type of locomotion. Classification This class was anticipated by some biologists like Jahn, who grouped all amoebae with granular pseudopodia together, but most split the lobose amoebae into testate Testacealobosia and naked Gymnamoebia. These latter are polyphyletic, but molecular trees by Bolivar ''et al.'' identified a core monophyletic subgroup. Subsequent studies showed the testate lobose amoebae belong to the same group, which was thus renamed Lobosea ''sensu stricto'' or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archamoebea
The Archamoebae are a group of protists originally thought to have evolved before the acquisition of mitochondria by eukaryotes. They include genera that are internal parasites or commensals of animals (''Entamoeba'' and ''Endolimax''). A few species are human pathogens, causing diseases such as amoebic dysentery. The other genera of archamoebae live in freshwater habitats and are unusual among amoebae in possessing flagella. Most have a single nucleus and flagellum, but the giant amoeba '' Pelomyxa'' has many of each. Description Archamoebae are a diverse group of amoebae. Many have flagella for motility, while others do not. They grow in the absence of oxygen, though some can tolerate small amounts. Most described species of Archamoebae either lack mitochondria or are described to have reduced mitosomes. Habitat They thrive and live in soil, freshwater, and marine habitats. History The group Archamoebae was proposed by Thomas Cavalier-Smith in 1998 as part of the Archezoa, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archamoebae
The Archamoebae are a group of protists originally thought to have evolved before the acquisition of mitochondria by eukaryotes. They include genera that are internal parasites or commensals of animals (''Entamoeba'' and ''Endolimax''). A few species are human pathogens, causing diseases such as amoebic dysentery. The other genera of archamoebae live in freshwater habitats and are unusual among amoebae in possessing flagella. Most have a single nucleus and flagellum, but the giant amoeba '' Pelomyxa'' has many of each. Description Archamoebae are a diverse group of amoebae. Many have flagella for motility, while others do not. They grow in the absence of oxygen, though some can tolerate small amounts. Most described species of Archamoebae either lack mitochondria or are described to have reduced mitosomes. Habitat They thrive and live in soil, freshwater, and marine habitats. History The group Archamoebae was proposed by Thomas Cavalier-Smith in 1998 as part of the Archezoa, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kingdom (biology)
In biology, a kingdom is the second highest taxonomic rank, just below domain. Kingdoms are divided into smaller groups called phyla. Traditionally, some textbooks from the United States and Canada used a system of six kingdoms (Animalia, Plantae, Fungi, Protista, Archaea/Archaebacteria, and Bacteria/Eubacteria) while textbooks in Great Britain, India, Greece, Brazil and other countries use five kingdoms only (Animalia, Plantae, Fungi, Protista and Monera). Some recent classifications based on modern cladistics have explicitly abandoned the term ''kingdom'', noting that some traditional kingdoms are not monophyletic, meaning that they do not consist of all the descendants of a common ancestor. The terms '' flora'' (for plants), ''fauna'' (for animals), and, in the 21st century, '' funga'' (for fungi) are also used for life present in a particular region or time. Definition and associated terms When Carl Linnaeus introduced the rank-based system of nomenclature into b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
