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Katabia
''Katabia'' is a genus of soil-dwelling heterotrophic flagellate Cercozoa, cercozoans containing the Monotypic taxon, single species ''Katabia gromovi'', and the only member of family Katabiidae. Morphology ''Katabia'' are drop-shaped unicellular flagellates with a broad anterior end and a tapering posterior end. They have two heterodynamic (with different movements) flagellum, flagella. Inside their cells are a microbody, refractile granules shaped like mushrooms, kinetocysts and a well-developed cytoskeleton similar to the one found in ''Heteromita''. Their life cycle has two forms: a free-living trophozoite that feeds on bacteria through pseudopodia while swimming, and a Microbial cyst, cyst that is surrounded by a thick mucilage-like wall. Instead of gliding upon the substrate, like other Cercozoa, cercozoans, they have secondarily lost the ability to glide with cilium, cilia, and only swim freely using their flagella. In particular, the species ''Katabia gromovi'' is a soil- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Katabia Gromovi Full 2003
''Katabia'' is a genus of soil-dwelling heterotrophic flagellate cercozoans containing the single species ''Katabia gromovi'', and the only member of family Katabiidae. Morphology ''Katabia'' are drop-shaped unicellular flagellates with a broad anterior end and a tapering posterior end. They have two heterodynamic (with different movements) flagella. Inside their cells are a microbody, refractile granules shaped like mushrooms, kinetocysts and a well-developed cytoskeleton similar to the one found in ''Heteromita''. Their life cycle has two forms: a free-living trophozoite that feeds on bacteria through pseudopodia while swimming, and a cyst that is surrounded by a thick mucilage-like wall. Instead of gliding upon the substrate, like other cercozoans, they have secondarily lost the ability to glide with cilia, and only swim freely using their flagella. In particular, the species ''Katabia gromovi'' is a soil-dwelling flagellate with a prominent dorsal side and a flattened ven ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarcomonadea
The sarcomonads () or class Sarcomonadea are a group of amoeboid biciliate protists in the phylum Cercozoa. They are characterized by a propensity to move through gliding on their posterior cilium or through filopodia, a lack of scales or external theca, a soft cell surface without obvious cortical filamentous or membranous skeleton, two cilia without scales or hairs, tubular mitochondrial cristae, near-spherical extrusomes, and a microbody (probably a peroxisome) attached to the nucleus. History In 1993 Cavalier-Smith described the sarcomonads as a subclass known as “Sarcomonadia”, an assemblage of unrelated cercozoans (thaumatomonads, proteomyxids, cercomonads...) and excavates ( jakobids), in the now defunct class “Heteromitea”, in the old phylum “ Opalozoa”. This subclass was created to lump together protozoa that have an anisokont type of zoospore (i.e. two cilia of different lengths), are non- thecate and have isodiametric extrusomes. Sarcomonadia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epithet
An epithet (, ), also byname, is a descriptive term (word or phrase) known for accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, divinities, objects, and binomial nomenclature. It can also be a descriptive title: for example, Pallas Athena, Phoebus Apollo, Alfred the Great, Suleiman the Magnificent, and Władysław I the Elbow-high. Many English monarchs have traditional epithets: some of the best known are Edward the Confessor, William the Conqueror, Richard the Lionheart, Æthelred the Unready, John Lackland and Bloody Mary. The word ''epithet'' can also refer to an abusive, defamatory, or derogatory phrase. This use as a euphemism is criticized by Martin Manser and other proponents of linguistic prescription. H. W. Fowler complained that "epithet is suffering a vulgarization that is giving it an abusive imputation." Linguistics Epithets are somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glissomonadida
The glissomonads are a group of bacterivorous gliding motility, gliding flagellated protists that compose the order (biology), order Glissomonadida, in the amoeboflagellate phylum Cercozoa. They comprise a vast, largely undescribed diversity of soil and freshwater organisms. They are the sister group to cercomonads; the two orders form a solid clade of gliding soil-dwelling flagellates called Pediglissa. Morphology External appearance Glissomonads are zooflagellates that aren't strongly amoeboid, and are only covered by a plasma membrane. Their common ancestor is thought to be a biflagellate, with a short anterior (anatomy), anterior flagellum and a long posterior (anatomy), posterior flagellum, that gliding motility, glided on the substrate by moving their posterior flagellum. In gliding descendants, the cell's posterior zone is usually rounded, giving the cell an ovoid shape. Some species may temporarily extend a protoplasmic tail, that unlike most cercomonads doesn't trail along ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cercomonadida
Cercomonads are small flagellates, widespread in aqueous habitats and common in soils. Characteristics The cells are generally around 10 μm in length, without any shell or covering. They produce filose pseudopods to capture bacteria, but do not use them for locomotion, which usually takes place by gliding along surfaces. Most members have two flagella, one directed forward and one trailing under the cell, inserted at right angles near its anterior. The nucleus is connected to the flagellar bases and accompanied by a characteristic paranuclear body. Classification Genetic studies place the cercomonads among the Cercozoa, a diverse group of amoeboid and flagellate protozoans. They are divided into two families. * The Heteromitidae tend to be relatively rigid, and produce only temporary pseudopods. * The Cercomonadidae are more plastic, and when food supplies are plentiful may become amoeboid and even multinucleate. The classification of genera and species continues to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incertae Sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty at specific taxonomic levels is indicated by ' (of uncertain family), ' (of uncertain suborder), ' (of uncertain order) and similar terms. Examples *The fossil plant '' Paradinandra suecica'' could not be assigned to any family, but was placed ''incertae sedis'' within the order Ericales when described in 2001. * The fossil '' Gluteus minimus'', described in 1975, could not be assigned to any known animal phylum. The genus is therefore ''incertae sedis'' within the kingdom Animalia. * While it was unclear to which order the New World vultures (family Cathartidae) should be assigned, they were placed in Aves ''incertae sedis''. It was later agreed to place them in a separate order, Cathartiformes. * Bocage's longbill, ''Motacilla boc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology is a branch of biology dealing with the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance ( shape, structure, colour, pattern, size), i.e. external morphology (or eidonomy), as well as the form and structure of the internal parts like bones and organs, i.e. internal morphology (or anatomy). This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cercomonadida
Cercomonads are small flagellates, widespread in aqueous habitats and common in soils. Characteristics The cells are generally around 10 μm in length, without any shell or covering. They produce filose pseudopods to capture bacteria, but do not use them for locomotion, which usually takes place by gliding along surfaces. Most members have two flagella, one directed forward and one trailing under the cell, inserted at right angles near its anterior. The nucleus is connected to the flagellar bases and accompanied by a characteristic paranuclear body. Classification Genetic studies place the cercomonads among the Cercozoa, a diverse group of amoeboid and flagellate protozoans. They are divided into two families. * The Heteromitidae tend to be relatively rigid, and produce only temporary pseudopods. * The Cercomonadidae are more plastic, and when food supplies are plentiful may become amoeboid and even multinucleate. The classification of genera and species continues to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protistology
Protistology is a scientific discipline devoted to the study of protists, a highly diverse group of eukaryotic organisms. All eukaryotes apart from animals, plants and fungi are considered protists. Its field of study therefore overlaps with the more traditional disciplines of phycology, mycology, and protozoology, just as protists embrace mostly unicellular organisms described as algae, some organisms regarded previously as primitive fungi, and protozoa ("animal" motile protists lacking chloroplasts). They are a paraphyletic group with very diverse morphologies and lifestyles. Their sizes range from unicellular picoeukaryotes only a few micrometres in diameter to multicellular marine algae several metres long. History The term " protozoology" has become dated as understanding of the evolutionary relationships of the eukaryotes has improved, and is frequently replaced by the term "protistology". For example, the Society of Protozoologists, founded in 1947, was renamed Intern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microbiology
Microbiology () is the scientific study of microorganisms, those being unicellular (single cell), multicellular (cell colony), or acellular (lacking cells). Microbiology encompasses numerous sub-disciplines including virology, bacteriology, protistology, mycology, immunology, and parasitology. Eukaryotic microorganisms possess membrane-bound organelles and include fungi and protists, whereas prokaryotic organisms—all of which are microorganisms—are conventionally classified as lacking membrane-bound organelles and include Bacteria and Archaea. Microbiologists traditionally relied on culture, staining, and microscopy. However, less than 1% of the microorganisms present in common environments can be cultured in isolation using current means. Microbiologists often rely on molecular biology tools such as DNA sequence based identification, for example the 16S rRNA gene sequence used for bacteria identification. Viruses have been variably classified as organisms, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Russia
Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eighth of Earth's inhabitable landmass. Russia extends across eleven time zones and shares land boundaries with fourteen countries, more than any other country but China. It is the world's ninth-most populous country and Europe's most populous country, with a population of 146 million people. The country's capital and largest city is Moscow, the largest city entirely within Europe. Saint Petersburg is Russia's cultural centre and second-largest city. Other major urban areas include Novosibirsk, Yekaterinburg, Nizhny Novgorod, and Kazan. The East Slavs emerged as a recognisable group in Europe between the 3rd and 8th centuries CE. Kievan Rus' arose as a state in the 9th century, and in 988, it adopted Orthodox Christianity from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
