|
Euplotidium
''Euplotidium'' is a genus of ciliates. Species form symbiotic relations with bacteria in structures named ''Epixenosomes Epixenosomes, also known as Candidatus ''Epixenosoma'' are a genus of bacteria in the phylum Verrucomicrobiota that form a symbiosis with marine ciliates of the genus '' Euplotidium'', where they help to defend their ciliate hosts against predat ...''. References Hypotrichea Ciliate genera Symbiosis {{ciliate-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epixenosomes
Epixenosomes, also known as Candidatus ''Epixenosoma'' are a genus of bacteria in the phylum Verrucomicrobiota that form a symbiosis with marine ciliates of the genus '' Euplotidium'', where they help to defend their ciliate hosts against predators. It is a monospecific genus, containing only the species Ca. ''Epixenosoma ejectans''. Description Epixenosomes possess two distinct developmental phases linked to the host cell cycle. Stage I epixenosomes are spherical, 0.5 μm in diameter and are surrounded by two membranes. They divide by direct binary fission. Stage II epixenosomes are egg-shaped (2.2 μm in length and 1 μm in width) and show complex organization with different cytoplasmic compartments, more complicated than the majority of prokaryotic organisms. They contain an extrusive apparatus within a proteinaceous matrix, although apparently not membrane-bound, which differs from the remaining cytoplasm. A functional cell compartmentalization has also been evidenced. Thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard archaea. This implies that there are only two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as Flagellated cell, flagellated phagotrophs. Their name comes from the Greek language, Greek wikt:εὖ, εὖ (''eu'', "well" or "good") and wikt:� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SAR Supergroup
The SAR supergroup, also just SAR or Harosa, is a clade that includes stramenopiles (heterokonts), alveolates, and Rhizaria. The name is an acronym derived from the first letters of each of these clades; it has been alternatively spelled "RAS". The term "Harosa" (at the subkingdom level) has also been used. The SAR supergroup is a node-based taxon. Note that as a formal taxon, "Sar" has only its first letter capitalized, while the earlier abbreviation, SAR, retains all uppercase letters. Both names refer to the same group of organisms, unless further taxonomic revisions deem otherwise. Members of the SAR supergroup were once included under the separate supergroups Chromalveolata ( Chromista and Alveolata) and Rhizaria, until phylogenetic studies confirmed that stramenopiles and alveolates diverged with Rhizaria. This apparently excluded haptophytes and cryptomonads, leading Okamoto ''et al.'' (2009) to propose the clade Hacrobia to accommodate them. Phylogeny Based on a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciliate
The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general shorter and present in much larger numbers, with a different undulating pattern than flagella. Cilia occur in all members of the group (although the peculiar Suctoria only have them for part of their life cycle) and are variously used in swimming, crawling, attachment, feeding, and sensation. Ciliates are an important group of protists, common almost anywhere there is water—in lakes, ponds, oceans, rivers, and soils. About 4,500 unique free-living species have been described, and the potential number of extant species is estimated at 27,000–40,000. Included in this number are many ectosymbiotic and endosymbiotic species, as well as some obligate and opportunistic parasites. Ciliate species range in size from as little as 10 µm in some colpodeans to as much as 4 mm in length in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypotrichia
The hypotrichs are a group of ciliated protozoa, common in fresh water, salt water, soil and moss. Hypotrichs possess compound ciliary organelles called "cirri," which are made up of thick tufts of cilia, sparsely distributed on the ventral surface of the cell. The multiple fused cilia which form a cirrus function together as a unit, enabling the organism to crawl along solid substrates such as submerged debris or sediments. Hypotrichs typically possess a large oral aperture, bordered on one side by a wreath or collar of membranelles (small membranous structures made up of fused cilia), forming an "adoral zone of membranelles," or AZM. Classification In older systems of classification, the term hypotrich comprised all ciliates possessing a relatively flattened body shape, strong cirri restricted to the ventral surface, and a large oral region (peristome) partially surrounded by an "adoral zone of membranelles". From a phylogenetic point of view, this historic grouping--which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
