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Bassia (cnidarian)
''Bassia'' is a monotypic siphonophore genus in the family Abylidae. The genus contains the single species ''Bassia bassensis''. Description The species reaches body lengths of 6–8 cm. The body plan is radially symmetric around a central mouth, with a polyhedral shape bearing 4 main ridges which end in short basal teeth. The species is bioluminescent and has a bluish tint on the ridges of the nectophores and is covered in gelatinous sheets that form a “box” around the mouth. As in all cnidarians, there is a single gastrovascular cavity (the coelenteron) and the mouth acts as both mouth and anus; it is surrounded by a layer of tentacles bearing nematocysts. Distribution ''Bassia bassensis'' is common in warmer and tropical waters in the Atlantic and Pacific oceans, specifically around the African and Asian coasts. It is common in the Humboldt Current system, along with other gelatinous zooplankton off the coast of South America, where three currents mix togeth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean René Constant Quoy
Jean René Constant Quoy (10 November 1790 in Maillé – 4 July 1869 in Rochefort) was a French naval surgeon, zoologist and anatomist. In 1806, he began his medical studies at the school of naval medicine at Rochefort, afterwards serving as an auxiliary-surgeon on a trip to the Antilles (1808–1809). After earning his medical doctorate in 1814 at Montpellier, he was surgeon-major on a journey to Réunion (1814–1815). Along with Joseph Paul Gaimard, he served as naturalist and surgeon aboard the ''Uranie'' under Louis de Freycinet from 1817 to 1820, and on the ''Astrolabe'' (1826–1829) under the command of Jules Dumont d'Urville. In July 1823 he and Gaimard presented a paper to the Académie royale des Sciences on the origin of coral reefs, taking issue with the then widespread belief that these were constructed by coral polyps from bases in very deep water and arguing instead that the original bases must have been in shallow water because reef-building polyps were con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bioluminescent
Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus ''Vibrio''; in others, it is autogenic, produced by the animals themselves. In a general sense, the principal chemical reaction in bioluminescence involves a light-emitting molecule and an enzyme, generally called luciferin and luciferase, respectively. Because these are generic names, luciferins and luciferases are often distinguished by the species or group, e.g. firefly luciferin. In all characterized cases, the enzyme catalyzes the oxidation of the luciferin. In some species, the luciferase requires other cofactors, such as calcium or magnesium ions, and some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salinity
Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to ‰). Salinity is an important factor in determining many aspects of the chemistry of natural waters and of biological processes within it, and is a thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water. A contour line of constant salinity is called an ''isohaline'', or sometimes ''isohale''. Definitions Salinity in rivers, lakes, and the ocean is conceptually simple, but technically challenging to define and measure precisely. Conceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sodium bicarbonate which dissolve into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copepod
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ocean floor), a number of species have parasitic phases, and some continental species may live in limnoterrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds, and puddles, damp moss, or water-filled recesses (phytotelmata) of plants such as bromeliads and pitcher plants. Many live underground in marine and freshwater caves, sinkholes, or stream beds. Copepods are sometimes used as biodiversity indicators. As with other crustaceans, copepods have a larval form. For copepods, the egg hatches into a nauplius form, with a head and a tail but no true thorax or abdomen. The larva molts several times until it resembles the adult and then, after more molts, achieves adult development. The nauplius form is so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epipelagic
The photic zone, euphotic zone, epipelagic zone, or sunlight zone is the uppermost layer of a body of water that receives sunlight, allowing phytoplankton to perform photosynthesis. It undergoes a series of physical, chemical, and biological processes that supply nutrients into the upper water column. The photic zone is home to the majority of aquatic life due to the activity (primary production) of the phytoplankton. Photosynthesis in photic zone In the photic zone, the photosynthesis rate exceeds the respiration rate. This is due to the abundant solar energy which is used as an energy source for photosynthesis by primary producers such as phytoplankton. These phytoplankton grow extremely quickly because of sunlight's heavy influence, enabling it to be produced at a fast rate. In fact, ninety five percent of photosynthesis in the ocean occurs in the photic zone. Therefore, if we go deeper, beyond the photic zone, such as into the compensation point, there is little to no p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southern Subregion#Americas, subregion of a single continent called Americas, America. South America is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean; North America and the Caribbean Sea lie to the northwest. The continent generally includes twelve sovereign states: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela; two dependent territory, dependent territories: the Falkland Islands and South Georgia and the South Sandwich Islands; and one administrative division, internal territory: French Guiana. In addition, the ABC islands (Leeward Antilles), ABC islands of the Kingdom of the Netherlands, Ascension Island (dependency of Saint Helena, Asce ... [...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] |
Humboldt Current
The Humboldt Current, also called the Peru Current, is a cold, low-salinity ocean current that flows north along the western coast of South America.Montecino, Vivian, and Carina B. Lange. "The Humboldt Current System: Ecosystem components and processes, fisheries, and sediment studies." ''Progress in Oceanography'' 83.1 (2009): 65-79. DOI10.1016/j.pocean.2009.07.041/ref> It is an eastern boundary current flowing in the direction of the equator, and extends offshore. The Humboldt Current is named after the German naturalist Alexander von Humboldt even though it was discovered by José de Acosta 250 years before Humboldt. In 1846, von Humboldt reported measurements of the cold-water current in his book '' Cosmos''. The current extends from southern Chile (~45th parallel south) to northern Peru (~4th parallel south) where cold, upwelled, waters intersect warm tropical waters to form the Equatorial Front. Sea surface temperatures off the coast of Peru, around 5th parallel sout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nematocyst
A cnidocyte (also known as a cnidoblast or nematocyte) is an explosive cell containing one large secretory organelle called a cnidocyst (also known as a cnida () or nematocyst) that can deliver a sting to other organisms. The presence of this cell defines the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). Cnidae are used to capture prey and as a defense against predators. A cnidocyte fires a structure that contains a toxin within the cnidocyst; this is responsible for the stings delivered by a cnidarian. Structure and function Each cnidocyte contains an organelle called a cnida, cnidocyst, nematocyst, ptychocyst or spirocyst. This organelle consists of a bulb-shaped capsule containing a coiled hollow tubule structure attached to it. An immature cnidocyte is referred to as a cnidoblast or nematoblast. The externally oriented side of the cell has a hair-like trigger called a cnidocil, which is a mechano- and chemo-receptor. When the trigger is activated, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coelenteron
The gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Coelenterates or cnidarians (including jellyfish and corals) and Platyhelminthes (flatworms). The cavity may be extensively branched into a system of canals. In cnidarians, the gastrovascular system is also known as the coelenteron, and is commonly known as a "blind gut" or "blind sac", since food enters and waste exits through the same orifice. The radially symmetrical cnidarians have a sac-like body in two distinct layers, the epidermis and gastrodermis, with a jellylike layer called the mesoglea between. Extracellular digestion takes place within the central cavity of the sac-like body. This cavity has only one opening to the outside which, in most cnidarians, is surrounded by 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 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nectophore
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Abylidae
The Abylidae are a family of marine invertebrates in the order Siphonophorae. They are colonial, but the colonies can superficially resemble jellyfish; although they appear to be a single organism, each specimen is actually a colony of Siphonophora. It contains the following taxa: * Subfamily Abylinae L. Agassiz, 1862 ** Genus '' Abyla'' Quoy & Gaimard, 1827 *** '' Abyla bicarinata'' Moser, 1925 *** '' Abyla haeckeli'' Lens & van Reimsdijk, 1908 *** '' Abyla trigona'' Quoy & Gaimard, 1827 ** Genus '' Ceratocymba'' Chun, 1888 *** '' Ceratocymba dentata'' (Bigelow, 1918) *** '' Ceratocymba leuckarti'' (Huxley, 1859) *** '' Ceratocymba sagittata'' Quoy & Gaimard, 1827 * Subfamily Abylopsinae Totton, 1954 ** Genus ''Abylopsis'' Chun, 1888 *** ''Abylopsis eschscholtzi ''Abylopsis'' is a siphonophore genus in the Abylidae. The genus contains bioluminescent Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
