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Haplozoon
''Haplozoon'' (/hæploʊ’zoʊən/) are unicellular endo-parasites, primarily infecting maldanid polychaetes. They belong to Dinoflagellata but differ from typical dinoflagellates. Most dinoflagellates are free-living and possess two flagella. Instead, ''Haplozoon'' belong to a 5% minority of parasitic dinoflagellates that are not free-living. Additionally, the ''Haplozoon'' trophont stage is particularly unique due to an apparent lack of flagella. The presence of flagella or remnant structures is the subject of ongoing research. At first glance, ''Haplozoon'' also do not appear unicellular – in fact they were originally classified as a possible transitional stage between protists and multicellular organisms.Shumway, W. (1924). The genus ''Haplozoon'', Dogiel. Observations on the life history and systematic position. ''The Journal of Parasitology, 11''(2), 59-74. They have more recently been classified as compartmentalized syncytia – single cells with multiple nuclei that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blastodiniales
Blastodiniales is an order of dinoflagellates belonging to the class Dinophyceae Dinophyceae is a class of dinoflagellates. Taxonomy * Class Dinophyceae Pascher 1914 eridinea Ehrenberg 1830 stat. nov. Wettstein; Blastodiniphyceae Fensome et al. 1993 orthog. emend.** Order Haplozoonales aplozooidea Poche 1913*** Family Ha .... Families: * Apodiniaceae Chatton * Paradiniaceae J.Schiller * Haplozoonidae Chatton References {{Taxonbar, from=Q2839918 Dinophyceae Dinoflagellate orders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinophyceae
Dinophyceae is a class of dinoflagellates. Taxonomy * Class Dinophyceae Pascher 1914 eridinea Ehrenberg 1830 stat. nov. Wettstein; Blastodiniphyceae Fensome et al. 1993 orthog. emend.** Order Haplozoonales aplozooidea Poche 1913*** Family Haplozoonaceae Chatton 1920 ** Order Akashiwales *** Family Akashiwaceae ** Order Blastodiniales Chatton 1906 lastodinida Chatton 1906*** Family Blastodiniaceae Cavers 1913 ** Order Apodiniales *** Family Apodiniaceae Chatton 1920 ** Order Dinotrichales Pascher 1914 *** Family Crypthecodiniaceae Biecheler 1938 ex Chatton 1952 *** Family Dinotrichaceae Pascher 1914 ** Order Phytodiniales T. Christ. 1962 ex Loeblich 1970 inococcales Pascher 1914; Suessiales Fensome & al. 1993; Dinamoebales *** Family † Suessiaceae Fensome et al. 1993 *** Family Phytodiniaceae Klebs 1912 inococcaceae Fott 1960; Hemidiniaceae Bourrelly 1970; Borghiellaceae Moestrup, Lindberg & Daugbjerg 2009*** Family Symbiodiniaceae Fensome & al. 1993 ooxant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syncytium
A syncytium (; plural syncytia; from Greek: σύν ''syn'' "together" and κύτος ''kytos'' "box, i.e. cell") or symplasm is a multinucleate cell which can result from multiple cell fusions of uninuclear cells (i.e., cells with a single nucleus), in contrast to a coenocyte, which can result from multiple nuclear divisions without accompanying cytokinesis. The muscle cell that makes up animal skeletal muscle is a classic example of a syncytium cell. The term may also refer to cells interconnected by specialized membranes with gap junctions, as seen in the heart muscle cells and certain smooth muscle cells, which are synchronized electrically in an action potential. The field of embryogenesis uses the word ''syncytium'' to refer to the coenocytic blastoderm embryos of invertebrates, such as ''Drosophila melanogaster''. Physiological examples Protists In protists, syncytia can be found in some rhizarians (e.g., chlorarachniophytes, plasmodiophorids, haplosporidians) and ace ... [...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 phagotrophs. Their name comes from the Greek εὖ (''eu'', "well" or "good") and κάρυον (''karyon'', "nut" or "kernel"). E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sequencing
In genetics and biochemistry, sequencing means to determine the primary structure (sometimes incorrectly called the primary sequence) of an unbranched biopolymer. Sequencing results in a symbolic linear depiction known as a sequence which succinctly summarizes much of the atomic-level structure of the sequenced molecule. DNA sequencing DNA sequencing is the process of determining the nucleotide order of a given DNA fragment. So far, most DNA sequencing has been performed using the chain termination method developed by Frederick Sanger. This technique uses sequence-specific termination of a DNA synthesis reaction using modified nucleotide substrates. However, new sequencing technologies such as pyrosequencing are gaining an increasing share of the sequencing market. More genome data are now being produced by pyrosequencing than Sanger DNA sequencing. Pyrosequencing has enabled rapid genome sequencing. Bacterial genomes can be sequenced in a single run with several times co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blastodinium
''Blastodinium'' (also known as ''Blastodiniphycaea'') is a diverse genus of dinoflagellates and important parasites of planktonic copepods. They exist in either a parasitic stage, a trophont stage, and a dinospore stage. Although morphologically and functionally diverse, as parasites they live exclusively in the intestinal tract of copeods. Etymology ''Blastodinium'' is made up of the Greek prefix ‘blasto-’, meaning to germ/bud. This likely refers to its dinospore stage following ''Blasdotinium'' reproduction, where sporocytes appear to bud out of a cuticle. History of knowledge The ''Blastodinium'' taxonomy is entirely based on their morphology at the trophont stage with ''B. pruvoti'' being the type species of the group. In 1920, Chatton proposed 3 main groups which are consistent with today's molecular data; Spinoulsum, Contorum, and Mangini. Upon their discovery, it was recognized that ''Blastodinium'' organisms had features that distinguished them from the majority o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gymnodiniales
The Gymnodiniales are an order of dinoflagellates, of the class Dinophyceae. Members of the order are known as gymnodinioid or gymnodinoid (terms that can also refer to any organism of similar morphology). They are athecate, or lacking an armored exterior, and as a result are relatively difficult to study because specimens are easily damaged. Many species are part of the marine plankton and are of interest primarily due to being found in algal blooms. As a group the gymnodinioids have been described as "likely one of the least known groups of the open ocean phytoplankton." Of the families in the order, the Polykrikaceae and Warnowiaceae are well known for possessing exceptionally complex assemblies of organelles, such as nematocysts, trichocysts, and pistons. The Warnowiaceae uniquely possess an ocelloid, an extremely complex light-sensitive subcellular structure composed of mitochondria and plastid The plastid (Greek: πλαστός; plastós: formed, molded – plural plastids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmission Electron Microscopy
Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a grid. An image is formed from the interaction of the electrons with the sample as the beam is transmitted through the specimen. The image is then magnified and focused onto an imaging device, such as a fluorescent screen, a layer of photographic film, or a sensor such as a scintillator attached to a charge-coupled device. Transmission electron microscopes are capable of imaging at a significantly higher resolution than light microscopes, owing to the smaller de Broglie wavelength of electrons. This enables the instrument to capture fine detail—even as small as a single column of atoms, which is thousands of times smaller than a resolvable object seen in a light microscope. Transmission electron microscopy is a major analytical method ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Obligate Parasite
An obligate parasite or holoparasite is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host. If an obligate parasite cannot obtain a host it will fail to reproduce. This is opposed to a facultative parasite, which can act as a parasite but does not rely on its host to continue its life-cycle. Obligate parasites have evolved a variety of parasitic strategies to exploit their hosts. Holoparasites and some hemiparasites are obligate. It is advantageous for the parasite to preserve the health of their host when this is compatible with their nutritional and reproductive requirements, except when the death of the host is necessary for transmission.Combes, C. (1997) Fitness of Parasites: Pathology and Selection ''International Journal for Parasitology'' 27 (1): 1–10. Species Obligate parasitism is exhibited in a range of organisms, with examples in viruses, bacteria, fungi, plants, and animals.Balashov, Yu.S. (2011) Parasitism and Ecological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nomen Nudum
In taxonomy, a ''nomen nudum'' ('naked name'; plural ''nomina nuda'') is a designation which looks exactly like a scientific name of an organism, and may have originally been intended to be one, but it has not been published with an adequate description. This makes it a "bare" or "naked" name, which cannot be accepted as it stands. A largely equivalent but much less frequently used term is ''nomen tantum'' ("name only"). In zoology According to the rules of zoological nomenclature a ''nomen nudum'' is unavailable; the glossary of the ''International Code of Zoological Nomenclature'' gives this definition: And among the rules of that same Zoological Code: In botany According to the rules of botanical nomenclature a ''nomen nudum'' is not validly published. The glossary of the ''International Code of Nomenclature for algae, fungi, and plants'' gives this definition: The requirements for the diagnosis or description are covered by articles 32, 36, 41, 42, and 44. ''Nomina nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesozoa
The Mesozoa are minuscule, worm-like parasites of marine invertebrates. Generally, these tiny, elusive creatures consist of a somatoderm (outer layer) of ciliated cells surrounding one or more reproductive cells. A recent study recovered Mesozoa as a monophyletic group that emerged in the Lophotrochozoa as sister of the Rouphozoa. Some workers previously classified Mesozoa as the sole phylum of the lonely subkingdom Agnotozoa. Cavalier-Smith argued that at least some of the mesozoans are in fact protistans, not animals. In the 19th century, the Mesozoa were a wastebasket taxon for multicellular organisms which lacked the invaginating gastrula which was thought to define the Metazoa. Evolution Mesozoa were once thought to be evolutionary intermediate forms between Protozoans and Metazoans, but now they are thought to be degenerate or simplified metazoa. Their ciliated larvae are similar to the miracidium of trematodes, and their internal multiplication is similar to wha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
