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Acrasis
The family Acrasidae (ICZN, or Acrasiomycota, ICBN) is a family of slime molds which belongs to the excavate group Heterolobosea. The name element - comes from the Greek ''akrasia'', meaning "acting against one's judgement". This group consists of cellular slime molds. The terms "Acrasiomycota" or "Acrasiomycetes" have been used when the group was classified as a fungus ("-mycota"). In some classifications, ''Dictyostelium'' was placed in Acrasiomycetes, an artificial group of cellular slime molds, which was characterized by the aggregation of individual amoebae into a multicellular fruiting body, making it an important factor that related the acrasids to the dictyostelids. Each cell keeps its individuality even when it forms a stalk and fruiting body to reproduce. Slime molds were originally thought to be in a monophyletic group ''Mycetozoa'', with little distinction between ''Acrasis'' and ''Dictyostelids'', however scientists uncovered that they were distinct groups, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acrasis Rosea
Amoebae emerging from spores ''Acrasis rosea'' is a species of slime mold within the heterolobosea Heterolobosea are a class of Percolozoa. The only member of this class that is infectious to humans is '' Naegleria fowleri'', the causative agent of the often fatal disease amoebic meningitis. Typically, their life cycle alternates between fl .... References Further reading * * Percolozoa {{Excavata-stub ... [...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] |
Pocheina Rosea
''Pocheina rosea'' is a species of amoeboid protist in the genus '' Pocheina'', belonging to the order Acrasida. Originally described as ''Guttulina rosea'' by Cienkowski in 1873, the organism was reassigned to the genus ''Pocheina'' due to a preexisting use of the name ''Guttulina'' for a foraminiferan genus. ''P. rosea'' is recognized for its characteristic fruiting body morphology and is one of the two species known in its genus, the other being ''Pocheina flagellata.'' Morphology The characteristics of ''Pocheina rosea'' are pinkish to reddish. This is where the species name, ''rosea'', originates. The color appears due to the presence of intracellular pigments, but it was not specifically attributed to carotenoids in the reviewed studies. The fruiting body, sorocarp, of ''P. rosea'' consists of short stalk formed by a row of wedge-shaped cells, topped with a globose spore mass. The structure is distinct from that of ''Acrasis'' species, which typically form linear chains of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Percolozoa
The Percolozoa are a group of colourless, non-photosynthetic excavates, including many that can transform between amoeboid, flagellate, and cyst stages. Characteristics Most Percolozoa are found as bacterivores in soil, fresh water and occasionally in the ocean. The only member of this group that is infectious to humans is '' Naegleria fowleri'', the causative agent of the often fatal disease amoebic meningitis. The group is closely related to the Euglenozoa, and share with them the unusual characteristic of having mitochondria with discoid cristae. The presence of a ventral feeding groove in the flagellate stage, as well as other features, suggests that they are part of the Excavata group. The amoeboid stage is roughly cylindrical, typically around 20–40 μm in length. They are traditionally considered lobose amoebae, but are not related to the others, and unlike them, do not form true lobose pseudopods. Instead, they advance by eruptive waves, where hemispherical bulges ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slime Mold
Slime mold or slime mould is an informal name given to a polyphyletic assemblage of unrelated eukaryotic organisms in the Stramenopiles, Rhizaria, Discoba, Amoebozoa and Holomycota clades. Most are near-microscopic; those in the Myxogastria form larger plasmodial slime molds visible to the naked eye. The slime mold life cycle includes a free-living single-celled stage and the formation of spores. Spores are often produced in macroscopic multicellular or multinucleate fruiting bodies that may be formed through aggregation or fusion; aggregation is driven by chemical signals called acrasins. Slime molds contribute to the decomposition of dead vegetation; some are parasitic. Most slime molds are terrestrial and free-living, typically in damp shady habitats such as in or on the surface of rotting wood. Some myxogastrians and protostelians are aquatic or semi-aquatic. The phytomyxea are parasitic, living inside their plant hosts. Geographically, slime molds are cosmopo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterolobosea
Heterolobosea are a class of Percolozoa. The only member of this class that is infectious to humans is '' Naegleria fowleri'', the causative agent of the often fatal disease amoebic meningitis. Typically, their life cycle alternates between flagellate and amoeboid stages. Etymology Life Cycle Characteristics Phylogeny The first broadly sampled comprehensive phylogenomic (phylotranscriptomic) analysis of the group (from 2025) confirmed the monophyly of Heterolobosea and provided a robustly supported backbone of the phylogeny resulting in the revision of the classification of Heterolobosea to the family level. The basal split of the cladogram has been confirmed between the subphyla Pharyngomonada (monotypic, with a sole family Pharyngomonadidae) and Tetramitia. In Tetramitia, two main clades (new classes) were identified: Selenaionea, consisting of two orders Neovahlkampfiida and Selenaionida in previously unsuspected but fully supported sister relationship, and Eutetr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grex (biology)
A grex (also called a pseudoplasmodium, or slug) starts as a crowd of single-celled amoebae of the groups Acrasiomycota or Dictyosteliida; ''grex'' is the Latin word for ''flock''. The cells flock together, forming a mass that behaves as an organised, slug-like unit. Before they get stimulated to crowd together to form a grex, the amoebae simply wander as independent cells grazing on bacteria and other suitable food items. They continue in that way of life as long as conditions are favourable. When the amoebae are stressed, typically by a shortage of food, they form a grex. According to species and circumstances, details of the shape of the grex and how it may form will vary but typically the stressed amoebae first produce pheromone A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behav ... [...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] |
Mold (fungus)
A mold () or mould () is one of the structures that certain fungi can form. The dust-like, colored appearance of molds is due to the formation of spores containing fungal secondary metabolites. The spores are the dispersal units of the fungi. Not all fungi form molds. Some fungi form mushrooms; others grow as single cells and are called microfungi (for example yeasts). A large and taxonomically diverse number of fungal species form molds. The growth of hyphae results in discoloration and a fuzzy appearance, especially on food. The network of these tubular branching hyphae, called a mycelium, is considered a single organism. The hyphae are generally transparent, so the mycelium appears like very fine, fluffy white threads over the surface. Cross-walls (septa) may delimit connected compartments along the hyphae, each containing one or multiple, genetically identical nuclei. The dusty texture of many molds is caused by profuse production of asexual spores (conidia) form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
