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Catostylus Tagi
''Catostylus tagi'' is a species of jellyfish from warmer parts of the East Atlantic Ocean and since the 2000s also found in the Mediterranean Sea. It is the only member of the family Catostylidae that is found in Europe.Parracho, T.; and Z. Morais (2015). Catostylus tagi: partial rDNA sequencing and characterisation of nematocyte structures using two improvements in jellyfish sample preparation. J Venom Anim Toxins Incl Trop Dis. 21: 40. It has collagen in its bell which is currently being researched to see if it has biomedical uses as an intercellular matrix. The species is named after the Tagus river. Description Typical ''Catostylus'' with chunky appendages and tentacle to go with each. This jellyfish has a sting that causes light pain and a skin rash, but generally poses no serious threat. It is up to in bell diameter, but a more typical size is in diameter and in weight. Its colour is variable and can be blue-white, cream, brown, or off-white. The exumbrellar grooves ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoological Specimen
A zoological specimen is an animal or part of an animal preserved for scientific use. Various uses are: to verify the identity of a (species), to allow study, increase public knowledge of zoology. Zoological specimens are extremely diverse. Examples are bird and mammal study skins, mounted specimens, skeletal material, casts, pinned insects, dried material, animals preserved in liquid preservatives, and microscope slides. Natural history museums are repositories of zoological specimens Study skins Bird and mammal specimens are conserved as dry study skins, a form of taxidermy. The skin is removed from the animal's carcass, treated with absorbents, and filled with cotton or polyester batting (In the past plant fibres or sawdust were used). Bird specimens have a long, thin, wooden dowel wrapped in batting at their center. The dowel is often intentionally longer than the bird's body and exits at the animal's vent. This exposed dowel provides a place to handle the bird without dist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonad
A gonad, sex gland, or reproductive gland is a mixed gland that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. The male gonad, the testicle, produces sperm in the form of spermatozoa. The female gonad, the ovary, produces egg cells. Both of these gametes are haploid cells. Some hermaphroditic animals have a type of gonad called an ovotestis. Evolution It is hard to find a common origin for gonads, but gonads most likely evolved independently several times. Regulation The gonads are controlled by luteinizing hormone and follicle-stimulating hormone, produced and secreted by gonadotropes or gonadotrophins in the anterior pituitary gland. This secretion is regulated by gonadotropin-releasing hormone produced in the hypothalamus. Development Gonads start developing as a common primordium (an organ in the earliest stage of development), in the form of genital ridges, which ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viviana Alder
Viviana A. Alder (born 1957 in San Julián, Argentina) is an Argentinian researcher in Antarctica, best known for her research on marine microbiology. Alder is considered to be among the first group of Argentine female scientists to work in Antarctica. Early life and education Alder obtained a degree in Oceanography from the Universidad Nacional de la Patagonia in 1982, and received her doctorate in Biological Sciences from the University of Buenos Aires in 1995. Career and impact Alder's research investigates the impact of the Antarctic Circumpolar Current and also El Nino and La Nina on food web structure, species dispersal and population abundance through the investigation of planktonic marine microbial communities. She is based at the Instituto Antartico Argentino; CONICET (National Scientific and Technical Research Council). Alder has led over ten Antarctic field seasons with financial support from the Argentine Antarctic Institute (Instituto Antartico Argentino), the Eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denaturation (biochemistry)
In biochemistry, denaturation is a process in which proteins or nucleic acids lose the quaternary structure, tertiary structure, and secondary structure which is present in their native state, by application of some external stress or compound such as a strong acid or base, a concentrated inorganic salt, an organic solvent (e.g., alcohol or chloroform), agitation and radiation or heat. If proteins in a living cell are denatured, this results in disruption of cell activity and possibly cell death. Protein denaturation is also a consequence of cell death. Denatured proteins can exhibit a wide range of characteristics, from conformational change and loss of solubility to aggregation due to the exposure of hydrophobic groups. The loss of solubility as a result of denaturation is called ''coagulation''. Denatured proteins lose their 3D structure and therefore cannot function. Protein folding is key to whether a globular or membrane protein can do its job correctly; it must ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid ''residues'' form the second-largest component ( water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycine
Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid ( carbamic acid is unstable), with the chemical formula NH2‐ CH2‐ COOH. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (GGU, GGC, GGA, GGG). Glycine is integral to the formation of alpha-helices in secondary protein structure due to its compact form. For the same reason, it is the most abundant amino acid in collagen triple-helices. Glycine is also an inhibitory neurotransmitter – interference with its release within the spinal cord (such as during a '' Clostridium tetani'' infection) can cause spastic paralysis due to uninhibited muscle contraction. It is the only achiral proteinogenic amino acid. It can fit into hydrophilic or hydrophobic environments, due to its minimal side chain of only one hydrogen atom. History and etymology Glycine was discovered in 1820 by the French ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Snow
In the deep ocean, marine snow (also known as "ocean dandruff") is a continuous shower of mostly organic detritus falling from the upper layers of the water column. It is a significant means of exporting energy from the light-rich photic zone to the aphotic zone below, which is referred to as the biological pump. Export production is the amount of organic matter produced in the ocean by primary production that is not recycled ( remineralised) before it sinks into the aphotic zone. Because of the role of export production in the ocean's biological pump, it is typically measured in units of carbon (e.g. mg C m−2 d−1). The term was first coined by the explorer William Beebe as he observed it from his bathysphere. As the origin of marine snow lies in activities within the productive photic zone, the prevalence of marine snow changes with seasonal fluctuations in photosynthetic activity and ocean currents. Marine snow can be an important food source for organisms living in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. Phytoplankton obtain their energy through photosynthesis, as do trees and other plants on land. This means phytoplankton must have light from the sun, so they live in the well-lit surface layers ( euphotic zone) of oceans and lakes. In comparison with terrestrial plants, phytoplankton are distributed over a larger surface area, are exposed to less seasonal variation and have markedly faster turnover rates than trees (days versus decades). As a result, phytoplankton respond rapidly on a global scale to climate variations. Phytoplankton form the base of marine and freshwater food webs and are key players in the global carbon cycle. They account for about half of global photosynthetic activity and at least half of the oxygen production, despi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zooplankton
Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by currents in the ocean, or by currents in seas, lakes or rivers. Zooplankton can be contrasted with phytoplankton, which are the plant component of the plankton community ("phyto" comes from the Greek word for ''plant''). Zooplankton are heterotrophic (other-feeding), whereas phytoplankton are autotrophic (self-feeding). This means zooplankton cannot manufacture their own food but must eat other plants or animals instead — in particular they eat phytoplankton. Zooplankton are generally larger than phytoplankton, most are microscopic, but some (such as jellyfish) are macroscopic and can be seen with the naked eye. Many protozoans (single-celled protists that prey on other microscopic life) are zooplankton, including zooflagellat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catostylus
''Catostylus'' is a genus of jellyfish in the family Catostylidae. Species The following species are recognized in the genus Catostylus. World Register of Marine Species, accessed 2014-01-29 *'' Catostylus cruciatus'' (Lesson, 1830) *'' Catostylus mosaicus'' (Quoy & Gaimard) *'' Catostylus ornatellus'' (Vanhöffen, 1888) *'' |
Musée Zoologique De La Ville De Strasbourg
The Musée zoologique de la ville de Strasbourg is a natural history museum displaying the zoological collections of the city of Strasbourg, managed and curated by the University of Strasbourg. The museum is closed since September 2019 and until 2023 for renovation and enlargement. History In 1802, the city of Strasbourg purchased all of the natural history collections of Johann Hermann. When the University of Strasbourg was created anew in 1872, the management and curation of the museum was entrusted to it. A spacious new building was erected from 1890 to 1893 and the collection continued to grow. The museum has collections of birds, marine mammals, invertebrates and insects, with a very particular focus on Alsatian fauna. There is also a reconstruction of Johann Hermann's study, containing many documents and specimens of his time. Collections The collections include: *1,350,000 invertebrates *1,000,000 insects *18,000 birds *10,000 mammals *2,450 fish *1,300 reptiles and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tagus
The Tagus ( ; es, Tajo ; pt, Tejo ; see below) is the longest river in the Iberian Peninsula. The river rises in the Montes Universales near Teruel, in mid-eastern Spain, flows , generally west with two main south-westward sections, to empty into the Atlantic Ocean in Lisbon. Its drainage basin covers – exceeded in the peninsula only by the Douro. The river is highly used. Several dams and diversions supply drinking water to key population centres of central Spain and Portugal; dozens of hydroelectric stations create power. Between dams it follows a very constricted course, but after Almourol, Portugal it has a wide alluvial valley, prone to flooding. Its mouth is a large estuary culminating at the major port, and Portuguese capital, Lisbon. The source is specifically: in political geography, at the Fuente de García in the Frías de Albarracín municipality; in physical geography, within the notably high range, the Sistema Ibérico (Iberian System), of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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