|
Voromonas
''Voromonas'' is a genus of predatory alveolates. The genus and species were described by Mylnikov in 2000. It was originally described as ''Colpodella pontica'' but was later renamed by Cavalier-Smith and Chao in 2004. Taxonomy There is one species known in this genus. A DNA based analysis suggests that this species may be related to the '' Colpodella''. Feeding At the anterior end of the protozoan, this organism manifests a rostrum which contains a microtubular structure (the pseudoconoid) The pseudoconoid forms an open cone and which is located adjacent to microtubular bands, micronemes and rhoptries. The pseudoconoid begins near the kinetosomes of the flagella and passes along the flagellate pocket into the rostrum. While feeding on prey organisms the rostrum is inserted into the body of the prey and the cytoplasm is sucked out. Known prey organisms include bodonids, chrysomonads, percolomonads. Known non prey organisms include naked amoebas, ciliates, cryptomonad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colpodella
''Colpodella'' is a genus of alveolates comprising five species, and two further possible species: They share all the synapomorphies of apicomplexans, but are free-living, rather than parasitic. Many members of this genus were previously assigned to a different genus - '' Spiromonas''. The type species is ''Colpodella pugnax'' Cienkowski 1865. Description These are small ('Dingensia angusta'' (Dujardin 1841) Patterson & Zoelffel 1991 Species transferred to other genera: * ''Colpodella gonderi'' (Foissner & Foissner 1984) Simpson & Patterson 1996 as ''Microvorax gonderi'' (Foissner & Foissner 1984) Cavalier-Smith 2017 * ''Colpodella perforans'' (Hollande 1938) Patterson & Zölffel 1991 as ''Chilovora perforans'' (Hollande 1938) Cavalier-Smith & Chao 2004 * ''Colpodella pontica'' Mylnikov 2000 as '' Voromonas pontica'' (Mylnikov 2000) Cavalier-Smith & Chao 2004 * ''Colpodella pugnax'' Simpson & Patterson 1996 non Cienkowsky 1865 as '' Algovora pugnax'' (Simpson & Patterson 1996) Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Cavalier-Smith
Thomas (Tom) Cavalier-Smith, FRS, FRSC, NERC Professorial Fellow (21 October 1942 – 19 March 2021), was a professor of evolutionary biology in the Department of Zoology, at the University of Oxford. His research has led to discovery of a number of unicellular organisms (protists) and advocated for a variety of major taxonomic groups, such as the Chromista, Chromalveolata, Opisthokonta, Rhizaria, and Excavata. He was known for his systems of classification of all organisms. Life and career Cavalier-Smith was born on 21 October 1942 in London. His parents were Mary Maude (née Bratt) and Alan Hailes Spencer Cavalier Smith. He was educated at Norwich School, Gonville and Caius College, Cambridge (MA) in Biology and King's College London (PhD) in Zoology. He was under the supervision of Sir John Randall for his PhD thesis between 1964 and 1967; his thesis was entitled "''Organelle Development in'' Chlamydomonas reinhardii". From 1967 to 1969, Cavalier-S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microtubules
Microtubules are polymers of tubulin that form part of the cytoskeleton and provide structure and shape to eukaryotic cells. Microtubules can be as long as 50 micrometres, as wide as 23 to 27 nm and have an inner diameter between 11 and 15 nm. They are formed by the polymerization of a dimer of two globular proteins, alpha and beta tubulin into protofilaments that can then associate laterally to form a hollow tube, the microtubule. The most common form of a microtubule consists of 13 protofilaments in the tubular arrangement. Microtubules play an important role in a number of cellular processes. They are involved in maintaining the structure of the cell and, together with microfilaments and intermediate filaments, they form the cytoskeleton. They also make up the internal structure of cilia and flagella. They provide platforms for intracellular transport and are involved in a variety of cellular processes, including the movement of secretory vesicles, organel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microneme
Micronemes are secretory organelles, possessed by parasitic apicomplexans. Micronemes are located on the apical third of the protozoan body. They are surrounded by a typical unit membrane. On electron microscopy they have an electron-dense matrix due to the high protein content. They are specialized secretory organelles important for host-cell invasion and gliding motility. These organelles secrete several proteins such as the ''Plasmodium falciparum ''Plasmodium falciparum'' is a Unicellular organism, unicellular protozoan parasite of humans and is the deadliest species of ''Plasmodium'' that causes malaria in humans. The parasite is transmitted through the bite of a female ''Anopheles'' mos ...'' apical membrane antigen-1, or PfAMA1, and Erythrocyte family antigen, or EBA, family proteins. These proteins specialize in binding to erythrocyte surface receptors and facilitating erythrocyte entry. Only by this initial chemical exchange can the parasite enter into the er ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhoptries
A rhoptry is a specialized secretory organelle. They are club-shaped organelles connected by thin necks to the extreme apical pole of the parasite. These organelles, like micronemes, are characteristic of the motile stages of Apicomplexa protozoans. They can vary in number and shape and contain numerous enzymes that are released during the process of host penetration. The proteins they contain are important in the interaction between the host and the parasite, including the formation of the parasitophorous vacuole (PV). Characteristics Rhoptries are one of the three characteristic secretory organelles present in all Apicomplexa along with micronemes and dense granules. Rhoptries and micronemes are localized at the apical complex of the Apicomplexan organism, which suggests common ancestry of the members of the phylum and the evolution process they have experienced. The name rhoptry indicates its shape as it comes from the Greek word for “club-shaped.” These la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinetosome
A basal body (synonymous with basal granule, kinetosome, and in older cytological literature with blepharoplast) is a protein structure found at the base of a eukaryotic undulipodium (cilium or flagellum). The basal body was named by Theodor Wilhelm Engelmann in 1880. It is formed from a centriole and several additional protein structures, and is, essentially, a modified centriole. The basal body serves as a nucleation site for the growth of the axoneme microtubules. Centrioles, from which basal bodies are derived, act as anchoring sites for proteins that in turn anchor microtubules, and are known as the microtubule organizing center (MTOC). These microtubules provide structure and facilitate movement of vesicles and organelles within many eukaryotic cells. Assembly, structure Cilia and basal bodies form during quiescence or the G1 phase of the cell cycle. Before the cell enters G1 phase, i.e. before the formation of the cilium, the mother centriole serves as a component of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagella
A flagellum (; : flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores ( zoospores), and from a wide range of microorganisms to provide motility. Many protists with flagella are known as flagellates. A microorganism may have from one to many flagella. A gram-negative bacterium '' Helicobacter pylori'', for example, uses its flagella to propel itself through the stomach to reach the mucous lining where it may colonise the epithelium and potentially cause gastritis, and ulcers – a risk factor for stomach cancer. In some swarming bacteria, the flagellum can also function as a sensory organelle, being sensitive to wetness outside the cell. Across the three domains of Bacteria, Archaea, and Eukaryota, the flagellum has a different structure, protein composition, and mechanism of propulsion but shares the same function of providing motility. The Latin word means " whip" to describe its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bodonid
Bodonida is an order of kinetoplastid flagellate excavates. It contains the genera ''Bodo'' and '' Rhynchomonas'', relatives to the parasitic trypanosomes. This order also contains the colonial genus '' Cephalothamnium''. Taxonomy Bodonida contains the following suborders and families: * Eubodonina * Neobodonina ** Bodonidae Bütschli, 1887 ** Neobodonidae ** Rhynchomonadidae * Parabodonina ** Cryptobiidae Vickerman ** Parabodonidae Cavalier-Smith Thomas (Tom) Cavalier-Smith, Royal Society, FRS, Royal Society of Canada, FRSC, Natural Environment Research Council, NERC Professorial Fellow (21 October 1942 – 19 March 2021), was a professor of evolutionary biology in the Departme ... References Kinetoplastids Euglenozoa orders {{Excavata-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysomonad
The Chrysophyceae, usually called chrysophytes, chrysomonads, golden-brown algae, or golden algae, are a large group of algae, found mostly in freshwater. Golden algae is also commonly used to refer to a single species, '' Prymnesium parvum'', which causes fish kills. The Chrysophyceae should not be confused with the Chrysophyta, which is a more ambiguous taxon. Although "chrysophytes" is the anglicization of "Chrysophyta", it generally refers to the Chrysophyceae. Members Originally they were taken to include all such forms of the diatoms and multicellular brown algae, but since then they have been divided into several different groups (e.g., Haptophyceae, Synurophyceae) based on pigmentation and cell structure. Some heterotrophic flagellates as the bicosoecids and choanoflagellates were sometimes seen as related to golden algae too. They are now usually restricted to a core group of closely related forms, distinguished primarily by the structure of the flagella in motile cells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amoeba
An amoeba (; less commonly spelled ameba or amœba; : amoebas (less commonly, amebas) or amoebae (amebae) ), often called an amoeboid, is a type of Cell (biology), cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudopodia, pseudopods. Amoebae do not form a single Taxonomy (biology), taxonomic group; instead, they are found in every major Lineage (evolution), lineage of eukaryote, 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 (biology), class or subphylum Sarcodina, a grouping of Unicellular organism, single-celled organisms that possess pseudopods or move by protoplasmic flow. However, molecular phylogenetic studies have shown that Sarcodina is not a monophyletic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
