|
Gorgonin
Gorgonin is a flexible scleroprotein which provides structural strength to gorgonian corals, a subset of the order Alcyonacea. Gorgonian corals have supporting skeletal axes made of gorgonin and/or calcite. Gorgonin makes up the joints of bamboo corals in the deep sea, and forms the central internal skeleton of sea fans. It frequently contains appreciable quantities of bromine, iodine, and tyrosine. Gorgonin is diagenetically stable and is deposited in discrete annual growth rings in Primnoa resedaeformis, and possibly other species. History The study of the chemistry of gorgonin, as a substance rather than a protein, was started by Balard in 1825, who reported on the occurrence of "iodogorgic acid". Several sources cite Valenciennes as having given the protein the name of "gorgonin" in an 1855 monograph. However, the monograph cited appears to contradict this, solely naming a newly-discovered substance in Gorgonians "cornéine" after its resemblance to substances extracte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Fans
Alcyonacea is the old scientific order name for the informal group known as "soft corals". It is now an unaccepted name for class Octocorallia. It became deprecated . The following text should be considered a historical, outdated way of treating the taxonomy of Anthozoa and Octocorallia. Some, or many parts of it, are no longer valid. Any remaining information found to be still valid, should be carefully merged into Octocorallia. Alcyonacea are an order of sessile colonial cnidarians that are found throughout the oceans of the world, especially in the deep sea, polar waters, tropics and subtropics. Whilst not in a strict taxonomic sense, Alcyonacea are commonly known as soft corals. The term "soft coral" generally applies to organisms in the two orders Pennatulacea and Alcyonacea with their polyps embedded within a fleshy mass of coenenchymal tissue. Consequently, the term "gorgonian coral" is commonly handed to multiple species in the order Alcyonacea that produce a minera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcyonacea
Alcyonacea is the old scientific order name for the informal group known as "soft corals". It is now an unaccepted name for class Octocorallia. It became deprecated . The following text should be considered a historical, outdated way of treating the taxonomy of Anthozoa and Octocorallia. Some, or many parts of it, are no longer valid. Any remaining information found to be still valid, should be carefully merged into Octocorallia. Alcyonacea are an order of sessile colonial cnidarians that are found throughout the oceans of the world, especially in the deep sea, polar waters, tropics and subtropics. Whilst not in a strict taxonomic sense, Alcyonacea are commonly known as soft corals. The term "soft coral" generally applies to organisms in the two orders Pennatulacea and Alcyonacea with their polyps embedded within a fleshy mass of coenenchymal tissue. Consequently, the term "gorgonian coral" is commonly handed to multiple species in the order Alcyonacea that produce a min ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bamboo Coral
Bamboo coral, family Keratoisididae (formerly Isididae) is a family of coral of the phylum Cnidaria. It is a commonly recognized inhabitant of the deep sea, due to the clearly articulated skeletons of the species. Deep water coral species such as this are especially affected by the practice of bottom trawling. These organisms may be an important environmental indicator in the study of long term climate change, as some specimens of bamboo coral have been discovered that are 4,000 years old. Bamboo corals were previously defined to be the family Isididae, based on their articulated skeletons with proteinaceous joints, but this family was shown to be paraphyletic after it was found in 2021 that this had evolved at least five separate times. As of 2023, the taxonomy of bamboo corals is being actively revised. Description Relatively little is known about bamboo coral. The skeletons of bamboo coral are made up of calcium carbonate in the form of tree-like branches alternating with j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plexaurella
''Plexaurella'' is a genus of gorgonian-type octocorals in the family Plexauridae Plexauridae is a Family (biology), family of marine Colony (biology), colonial Octocorallia, octocorals in the phylum Cnidaria. Members of this family are found in shallow tropical and subtropical seas. Many species contain Symbiosis, symbiotic P .... Species of the genus are typically characterised by their slit-pores, however, there are some which lack this distinguishing feature (e.g. ''P. grisea'').Bayer, FM 1961. Shallow water Octocorallia of the West Indian Region. Studies of the fauna of Curacao and other Caribbean islands. 55. Sclerite examination is necessary for species identification, which reveals the characteristic 4-rayed 'butterfly' spicules of the cortex and the lack of purple sclerites in the axial sheath. Species The World Register of Marine Species lists the following species in the genus: *'' Plexaurella crassa'' (Ellis, 1756) *'' Plexaurella curvata'' Kunze, 1916 *'' Plexa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primnoa
''Primnoa'' also known as red tree coral, is a genus of Alcyonacea, soft corals and the type genus of the family Primnoidae . They are Sessility (motility), sessile, Benthic zone, benthic Cnidaria, cnidarians that can be found in the Pacific Ocean, North Pacific, North Atlantic, and Subantarctic South Pacific, and its members often play a vital ecological role as keystone species within their environment as a habitat and refuge for the megafauna that also inhabit those regions. This, in combination with their slow growth, makes the increasing disturbance to their habitats caused by fishing activities particularly impactful and difficult to recover from. Etymology The name ''Primnoa'' derives from the Greek language, Greek word Πρυμνὼ (''Prymno''), the name of an Oceanids, Oceanid. The name itself is derived from πρυμνός (''prymnos''), meaning “last”, “lowest”, and by extension, “deepest”. Taxonomy The genus ''Primnoa'' was first Species description ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoceanography
Paleoceanography is the study of the history of the oceans in the geologic past with regard to circulation, chemistry, biology, geology and patterns of sedimentation and biological productivity. Paleoceanographic studies using environment models and different proxies enable the scientific community to assess the role of the oceanic processes in the global climate by the re-construction of past climate at various intervals. Paleoceanographic research is also intimately tied to paleoclimatology. Source and methods of information Paleoceanography makes use of so-called proxy methods as a way to infer information about the past state and evolution of the world's oceans. Several geochemical proxy tools include long-chain organic molecules (e.g. alkenones), stable and radioactive isotopes, and trace metals. Additionally, sediment cores rich with fossils and shells (tests) can also be useful; the field of paleoceanography is closely related to sedimentology and paleontology. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoclimatology
Paleoclimatology ( British spelling, palaeoclimatology) is the scientific study of climates predating the invention of meteorological instruments, when no direct measurement data were available. As instrumental records only span a tiny part of Earth's history, the reconstruction of ancient climate is important to understand natural variation and the evolution of the current climate. Paleoclimatology uses a variety of proxy methods from Earth and life sciences to obtain data previously preserved within rocks, sediments, boreholes, ice sheets, tree rings, corals, shells, and microfossils. Combined with techniques to date the proxies, the paleoclimate records are used to determine the past states of Earth's atmosphere. The scientific field of paleoclimatology came to maturity in the 20th century. Notable periods studied by paleoclimatologists include the frequent glaciations that Earth has undergone, rapid cooling events like the Younger Dryas, and the rapid warming du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ectoderm
The ectoderm is one of the three primary germ layers formed in early embryonic development. It is the outermost layer, and is superficial to the mesoderm (the middle layer) and endoderm (the innermost layer). It emerges and originates from the outer layer of germ cells. The word ectoderm comes from the Greek language, Greek ''ektos'' meaning "outside", and ''derma'' meaning "skin".Gilbert, Scott F. Developmental Biology. 9th ed. Sunderland, MA: Sinauer Associates, 2010: 333-370. Print. Generally speaking, the ectoderm differentiates to form epithelial tissue, epithelial and nervous system, neural tissues (spinal cord, nerves and brain). This includes the Epidermis (skin), skin, linings of the mouth, anus, nostrils, sweat glands, hair and nails, and tooth enamel. Other types of epithelium are derived from the endoderm. In vertebrate embryos, the ectoderm can be divided into two parts: the dorsal surface ectoderm also known as the external ectoderm, and the neural plate, which inv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. It is the key structural material making up Scale (anatomy), scales, hair, Nail (anatomy), nails, feathers, horn (anatomy), horns, claws, Hoof, hooves, and the outer layer of skin in vertebrates. Keratin also protects epithelial cells from damage or stress. Keratin is extremely insoluble in water and organic solvents. Keratin monomers assemble into bundles to form intermediate filaments, which are tough and form strong mineralization (biology), unmineralized epidermal appendages found in reptiles, birds, amphibians, and mammals. Excessive keratinization participate in fortification of certain tissues such as in horns of cattle and rhinos, and armadillos' osteoderm. The only other biology, biological matter known to approximate the toughness of keratinized tissue is chitin. Keratin comes in two types: the primitive, softer forms found in all vertebrates and the harder, derived forms fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diagenesis
Diagenesis () is the process of physical and chemical changes in sediments first caused by water-rock interactions, microbial activity, and compaction after their deposition. Increased pressure and temperature only start to play a role as sediments become buried much deeper in the Earth's crust. In the early stages, the transformation of poorly consolidated sediments into sedimentary rock (lithification) is simply accompanied by a reduction in porosity and water expulsion (clay sediments), while their main mineralogical assemblages remain unaltered. As the rock is carried deeper by further deposition above, its organic content is progressively transformed into kerogens and bitumens. The process of diagenesis excludes surface alteration (weathering) and deep metamorphism. There is no sharp boundary between diagenesis and metamorphism, but the latter occurs at higher temperatures and pressures. Hydrothermal solutions, meteoric groundwater, rock porosity, permeability, dissolu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
