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Chromerida
Chromerida is a phylum of unicellular alveolates, which includes photosynthetic species '' Chromera velia'' and '' Vitrella brassicaformis''. General features of the phylum include spherical cells each with a thick cell wall, chloroplast present with chlorophyll a only (no chlorophyll b or c), and an internal developing flagellum at some lifestages. They often live in close association with corals, and studies suggest their closest relatives is the parasitic group Apicomplexa The Apicomplexa (also called Apicomplexia) are a large phylum of parasitic alveolates. Most of them possess a unique form of organelle that comprises a type of non-photosynthetic plastid called an apicoplast, and an apical complex structure. Th ..., which evolved from photosynthetic ancestors, making Chromerida the last remaining photosynthetic members of an otherwise parasitic branch within Alveolata. Carter Lab at University of Sydney has undertaken new experiments to isolate novel Chromerids, using t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitrella Brassicaformis
''Vitrella brassicaformis'' (CCMP3155) is a unicellular alga belonging to the eukaryotic supergroup Alveolata. ''V. brassicaformis'' and its closest known relative, '' Chromera velia,'' are the only two currently described members of the phylum Chromerida, which in turn constitutes part of the taxonomically unranked group Colpodellida. Chromerida is phylogenetically closely related to the phylum Apicomplexa, which includes ''Plasmodium'', the agent of malaria. Notably, both ''V. brassicaformis'' and ''C. velia'' are photosynthetic, each containing a complex secondary plastid. This characteristic defined the discovery of these so-called ' chromerids,' as their photosynthetic capacity positioned them to shed light upon the evolution of Apicomplexa's non-photosynthetic parasitism. Both genera lack chlorophyll ''b'' or '' c''; these absences link the two taxonomically, as algae bearing only chlorophyll ''a'' are rare amid the biodiversity of life. Despite their similarities, ''V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromera Velia
''Chromera velia'', also known as a "chromerid", is a unicellular photosynthetic organism in the superphylum Alveolata. It is of interest in the study of apicomplexan parasites, specifically their evolution and accordingly, their unique vulnerabilities to drugs. The discovery of ''C. velia'' has sparked renewed interest in protist research, concerning both algae and parasites, as well as free-living unicells. Strict separation of botanical protists ( algae) and zoological protists ( protozoa) has been conventional but ''C. velia'' may be regarded as a good example of a bridge linking both categories. ''C. velia'' has typical features of alveolates, being phylogenetically related to Apicomplexa (a subgroup of alveolates), and contains a photosynthetic plastid ( chloroplast) while the apicomplexans have a non-photosynthetic plastid called the apicoplast. ''C. velia'' is also related to another subgroup of alveolates, the dinoflagellates of which most are photosynthetic. ''C. ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromerida
Chromerida is a phylum of unicellular alveolates, which includes photosynthetic species '' Chromera velia'' and '' Vitrella brassicaformis''. General features of the phylum include spherical cells each with a thick cell wall, chloroplast present with chlorophyll a only (no chlorophyll b or c), and an internal developing flagellum at some lifestages. They often live in close association with corals, and studies suggest their closest relatives is the parasitic group Apicomplexa The Apicomplexa (also called Apicomplexia) are a large phylum of parasitic alveolates. Most of them possess a unique form of organelle that comprises a type of non-photosynthetic plastid called an apicoplast, and an apical complex structure. Th ..., which evolved from photosynthetic ancestors, making Chromerida the last remaining photosynthetic members of an otherwise parasitic branch within Alveolata. Carter Lab at University of Sydney has undertaken new experiments to isolate novel Chromerids, using t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexa
The Apicomplexa (also called Apicomplexia) are a large phylum of parasitic alveolates. Most of them possess a unique form of organelle that comprises a type of non-photosynthetic plastid called an apicoplast, and an apical complex structure. The organelle is an adaptation that the apicomplexan applies in penetration of a host cell. The Apicomplexa are unicellular and spore-forming. All species are obligate endoparasites of animals, except '' Nephromyces'', a symbiont in marine animals, originally classified as a chytrid fungus. Motile structures such as flagella or pseudopods are present only in certain gamete stages. The Apicomplexa are a diverse group that includes organisms such as the coccidia, gregarines, piroplasms, haemogregarines, and plasmodia. Diseases caused by Apicomplexa include: * Babesiosis (''Babesia'') * Malaria (''Plasmodium'') * Cryptosporidiosis (''Cryptosporidium parvum'') * Cyclosporiasis (''Cyclospora cayetanensis'') * Cystoisosporiasis (''Cystoisosp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
Eukaryotes () are organisms whose Cell (biology), cells have a cell nucleus, 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-domain system, 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), Asgard archaea. This implies that there are only Two-domain system, 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 (ecology), 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. The ... [...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 compi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylum
In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature for algae, fungi, and plants accepts the terms as equivalent. Depending on definitions, the animal kingdom Animalia contains about 31 phyla, the plant kingdom Plantae contains about 14 phyla, and the fungus kingdom Fungi contains about 8 phyla. Current research in phylogenetics is uncovering the relationships between phyla, which are contained in larger clades, like Ecdysozoa and Embryophyta. General description The term phylum was coined in 1866 by Ernst Haeckel from the Greek (, "race, stock"), related to (, "tribe, clan"). Haeckel noted that species constantly evolved into new species that seemed to retain few consistent features among themselves and therefore few features that distinguished them as a group ("a self-contained unity" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral
Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton. A coral "group" is a colony of very many genetically identical polyps. Each polyp is a sac-like animal typically only a few millimeters in diameter and a few centimeters in height. A set of tentacles surround a central mouth opening. Each polyp excretes an exoskeleton near the base. Over many generations, the colony thus creates a skeleton characteristic of the species which can measure up to several meters in size. Individual colonies grow by asexual reproduction of polyps. Corals also breed sexually by spawning: polyps of the same species release gametes simultaneously overnight, often around a full moon. Fertilized eggs form planulae, a mobile early form of the coral polyp which, when m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
