|
Clavularia Frankliniana
''Clavularia frankliniana'' is a species of colonial soft coral in the family Clavulariidae. It is found in the southern Atlantic Ocean and the waters around Antarctica. It was first described in 1902 by the French zoologist Louis Roule. Description ''Clavularia frankliniana'' is a stoloniferous soft coral. It forms small colonies of polyps with eight tentacles which are up to high and are usually white. Distribution and habitat ''Clavularia frankliniana'' is native to the Antarctic Peninsula, the coasts of the Antarctic continent and the nearby island groups. It occurs at depths down to about and grows on rocks or other hard substrates. Ecology This coral contains the chemical unpalatable chimyl alcohol for defensive purposes. This is insufficient to prevent the nudibranch Tritoniella belli from feeding on it, and the nudibranch incorporates the substance into its own tissues, making it distasteful to predatory starfish such as ''Odontaster validus ''Odontaster validus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louis Roule
Louis Roule (; 20 December 1861 – 30 July 1942) was a French zoologist born in Marseille. In 1881 he obtained a degree in natural sciences at Marseille, followed by his doctorate of sciences (1884) at Paris with a thesis on ascidians of coastal Provence. From 1885 he worked as a lecturer at the faculty of sciences in Toulouse, where in 1892 he became a professor. During the previous year (1891), he earned a doctorate in medicine. In 1910 he succeeded Léon Vaillant (1834–1914) as chair of zoology (reptiles and fish) at the Muséum national d'histoire naturelle in Paris, a position he would hold until 1937. During this time period he was also an instructor at the Institut National Agronomique (from 1925), and director of the laboratory of ichthyology at the École pratique des hautes études (EPHE). Works Roule's early research dealt largely with invertebrates. Later his focus turned to ichthyology, of which he had the opportunity to take inventory of large collections of mari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fission (biology)
Fission, in biology, is the division of a single entity into two or more parts and the regeneration of those parts to separate entities resembling the original. The object experiencing fission is usually a cell, but the term may also refer to how organisms, bodies, populations, or species split into discrete parts. The fission may be ''binary fission'', in which a single organism produces two parts, or ''multiple fission'', in which a single entity produces multiple parts. Binary fission Organisms in the domains of Archaea and Bacteria reproduce with binary fission. This form of asexual reproduction and cell division is also used by some organelles within eukaryotic organisms (e.g., mitochondria). Binary fission results in the reproduction of a living prokaryotic cell (or organelle) by dividing the cell into two parts, each with the potential to grow to the size of the original. Fission of prokaryotes The single DNA molecule first replicates, then attaches each copy to a differ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acodontaster Conspicuus
''Acodontaster conspicuus'' is a species of starfish in the family Odontasteridae. It is found in the Southern Ocean, in the waters off Antarctica and the island groups nearby. Description ''Acodontaster conspicuus'' grows to about 30 cm (12 in) in diameter. It has 5 arms and the body has a cushion-like appearance, being thick except around the margins where there is a thin flat area. The upper surface has radially arranged granulations. The colour varies but is usually orange or brown.Acodontaster conspicuus (Koehler, 1920) Antarctic Field Guide. Retrieved 2011-11-27. Distribution ''Acodontaster conspicuus'' is found in the cold seas around Antarctica, including the |
Odontaster Validus
''Odontaster validus'' is a species of sea star in the family Odontasteridae. Its range includes the Southern Ocean and the seas around the mainland and islands of Antarctica. Description ''Odontaster validus'' can grow to about 10 cm (4 in) in diameter. The disc is broad, thick and cushion-like, creased by interambulacral grooves. There is a large madreporite near the centre and the surface is covered in small granulations organised in radial rows. The five short arms are wide at the base tapering sharply and the tip is often raised off the substrate showing the pale coloured tube feet beneath. The colour of the upper or aboral surface is plain red while the underside is pink. Distribution ''Odontaster validus'' is the most common sea star found in Antarctica. Its range includes the Antarctic Peninsula, the South Shetland Islands, the South Orkney Islands, South Georgia and the South Sandwich Islands, the Shag Rocks, the Prince Edward Islands and Bouvet Island. It i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tritoniella Belli
''Tritoniella belli'' is a species of the nudibranch genus ''Tritoniella''. The species was described together with its synonym ''Tritoniella sinuata'' in 1907 by the British diplomat and malacologist Charles Eliot. It is found in the Southern Ocean along the coast of Antarctica and along the southern parts of the Scotia Arc The Scotia Arc is the island arc system forming the north, east and south border of the Scotia Sea. The northern border, the North Scotia Ridge, comprises (from west to east) Isla de los Estados at the tip of Tierra del Fuego, the Burdwood, Davis, ... in depths between and . Synonymy ''Tritoniella sinuata'' was synonymized by Wägele in 1989 after she found that differentiation by the characters Eliot described was impossible. She argued, that differences between specimens were caused by fixation and individual variability. References Gastropods described in 1907 Tritoniidae {{Tritoniidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nudibranch
Nudibranchs () are a group of soft-bodied marine gastropod molluscs which shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have been given colourful nicknames to match, such as "clown", "marigold", "splendid", "dancer", "dragon", or "sea rabbit". Currently, about 3,000 valid species of nudibranchs are known.Ocean Portal (2017)A Collage of Nudibranch Colors Smithsonian National Museum of Natural History. Retrieved 17 April 2018. The word "nudibranch" comes from the Latin "naked" and the Ancient Greek () "gills". Nudibranchs are often casually called sea slugs, as they are a family of opistobranchs (sea slugs), within the phylum Mollusca (molluscs), but many sea slugs belong to several taxonomic groups which are not closely related to nudibranchs. A number of these other sea slugs, such as the photosynthetic ''Sacoglossa'' and the colourful Aglajidae, are often confused with nudibranchs. Distribut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (biology)
In biology, a substrate is the surface on which an organism (such as a plant, fungus, or animal) lives. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock (its substrate) can be itself a substrate for an animal that lives on top of the algae. Inert substrates are used as growing support materials in the hydroponic cultivation of plants. In biology substrates are often activated by the nanoscopic process of substrate presentation. In agriculture and horticulture * Cellulose substrate * Expanded clay aggregate (LECA) * Rock wool * Potting soil * Soil In animal biotechnology Requirements for animal cell and tissue culture Requirements for animal cell and tissue culture are the same as described for plant cell, tissue and organ culture (In Vitro Culture Techniques: The Biotechnological Principles). Desirable requirements are (i) air conditioning of a room, (ii) hot room with temperature recorder, (iii) microscope r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tentacle
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work mainly like muscular hydrostats. Most forms of tentacles are used for grasping and feeding. Many are sensory organs, variously receptive to touch, vision, or to the smell or taste of particular foods or threats. Examples of such tentacles are the eyestalks of various kinds of snails. Some kinds of tentacles have both sensory and manipulatory functions. A tentacle is similar to a cirrus, but a cirrus is an organ that usually lacks the tentacle's strength, size, flexibility, or sensitivity. A nautilus has cirri, but a squid has tentacles. Invertebrates Molluscs Many molluscs have tentacles of one form or another. The most familiar are those of the pulmonate land snails, which usually have two sets of tentacles on the head: when extended ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyp (zoology)
A polyp in zoology is one of two forms found in the phylum Cnidaria, the other being the medusa. Polyps are roughly cylindrical in shape and elongated at the axis of the vase-shaped body. In solitary polyps, the aboral (opposite to oral) end is attached to the substrate by means of a disc-like holdfast called a pedal disc, while in colonies of polyps it is connected to other polyps, either directly or indirectly. The oral end contains the mouth, and is surrounded by a circlet of tentacles. Classes In the class Anthozoa, comprising the sea anemones and corals, the individual is always a polyp; in the class Hydrozoa, however, the individual may be either a polyp or a medusa, with most species undergoing a life cycle with both a polyp stage and a medusa stage. In class Scyphozoa, the medusa stage is dominant, and the polyp stage may or may not be present, depending on the family. In those scyphozoans that have the larval planula metamorphose into a polyp, the polyp, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
