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Chemosynthetic
In biochemistry, chemosynthesis is the biological conversion of one or more carbon-containing molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic compounds (e.g., hydrogen gas, hydrogen sulfide) or ferrous ions as a source of energy, rather than sunlight, as in photosynthesis. Chemoautotrophs, organisms that obtain carbon from carbon dioxide through chemosynthesis, are phylogenetically diverse. Groups that include conspicuous or biogeochemically-important taxa include the sulfur-oxidizing Gammaproteobacteria, the Campylobacterota, the Aquificota, the methanogenic archaea, and the neutrophilic iron-oxidizing bacteria. Many microorganisms in dark regions of the oceans use chemosynthesis to produce biomass from single-carbon molecules. Two categories can be distinguished. In the rare sites where hydrogen molecules (H2) are available, the energy available from the reaction between CO2 and H2 (leading to production of m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cold Seep
A cold seep (sometimes called a cold vent) is an area of the ocean floor where hydrogen sulfide, methane and other hydrocarbon-rich fluid seepage occurs, often in the form of a brine pool. ''Cold'' does not mean that the temperature of the seepage is lower than that of the surrounding sea water. On the contrary, its temperature is often slightly higher. The "cold" is relative to the very warm (at least ) conditions of a hydrothermal vent. Cold seeps constitute a biome supporting several endemic species. Cold seeps develop unique topography over time, where reactions between methane and seawater create carbonate rock formations and reefs. These reactions may also be dependent on bacterial activity. Ikaite, a hydrous calcium carbonate, can be associated with oxidizing methane at cold seeps. Types Types of cold seeps can be distinguished according to the depth, as shallow cold seeps and deep cold seeps. Cold seeps can also be distinguished in detail, as follows: * oil/gas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrothermal Vent
A hydrothermal vent is a fissure on the seabed from which geothermally heated water discharges. They are commonly found near volcanically active places, areas where tectonic plates are moving apart at mid-ocean ridges, ocean basins, and hotspots. Hydrothermal deposits are rocks and mineral ore deposits formed by the action of hydrothermal vents. Hydrothermal vents exist because the earth is both geologically active and has large amounts of water on its surface and within its crust. Under the sea, they may form features called black smokers or white smokers. Relative to the majority of the deep sea, the areas around hydrothermal vents are biologically more productive, often hosting complex communities fueled by the chemicals dissolved in the vent fluids. Chemosynthetic bacteria and Archaea form the base of the food chain, supporting diverse organisms, including giant tube worms, clams, limpets and shrimp. Active hydrothermal vents are thought to exist on Jupiter's moon Europa an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trophosome
A trophosome is a highly vascularised organ found in some animals that houses symbiotic bacteria that provide food for their host. Trophosomes are located in the coelomic cavity in the vestimentiferan tube worms (Siboglinidae, e.g. the giant tube worm ''Riftia pachyptila'') and in symbiotic flatworms of the genus ''Paracatenula''. Organization Initially, the trophosome in frenulates and vestimentiferans had been identified as a mesodermal tissue. The discovery of bacteria inside the trophosomal tissue only occurred in 1981 when the ultrastructure of trophosome of several frenulate species and of ''Sclerolinum brattstromi'' was studied. The bacteriocytes and symbionts composed of 70.5% and 24.1% of the trophosome's volume respectively. Generally, trophosome extends over the entire trunk region between the two longitudinal blood vessels from immediately posterior to the ventral ciliary band of the forepart to the posterior end of the trunk delineated by the septum between trunk and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Tube Worm
''Riftia pachyptila'', commonly known as the giant tube worm and less commonly known as the Giant beardworm, is a marine invertebrate in the phylum Annelida (formerly grouped in phylum Pogonophora and Vestimentifera) related to tube worms commonly found in the intertidal and pelagic zones. ''R. pachyptila'' lives on the floor of the Pacific Ocean near hydrothermal vents, the vents provide a natural ambient temperature in their environment ranging from 2 to 30 °C, at the same time it can tolerate extremely high hydrogen sulfide levels. These worms can reach a length of , and their tubular bodies have a diameter of . Its common name "giant tube worm" is, however, also applied to the largest living species of shipworm, ''Kuphus polythalamius'', which despite the name "worm", is a bivalve mollusc rather than an annelid. Discovery ''R. pachyptila'' was discovered in 1977 on an expedition of the American bathyscaphe DSV ''Alvin'' to the Galápagos Rift led by ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gammaproteobacteria
Gammaproteobacteria is a class of bacteria in the phylum Pseudomonadota (synonym Proteobacteria). It contains about 250 genera, which makes it the most genera-rich taxon of the Prokaryotes. Several medically, ecologically, and scientifically important groups of bacteria belong to this class. It is composed by all Gram-negative microbes and is the most phylogenetically and physiologically diverse class of Proteobacteria. These microorganisms can live in several terrestrial and marine environments, in which they play various important roles, including ''extreme environments'' such as hydrothermal vents. They generally have different shapes - rods, curved rods, cocci, spirilla, and filaments and include free living bacteria, biofilm formers, commensals and symbionts, some also have the distinctive trait of being bioluminescent. Metabolisms found in the different genera are very different; there are both aerobic and anaerobic (obligate or facultative) species, chemolithoautotrophic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whale Fall
A whale fall occurs when the carcass of a whale has fallen onto the ocean floor at a depth greater than , in the bathyal or abyssal zones. On the sea floor, these carcasses can create complex localized ecosystems that supply sustenance to deep-sea organisms for decades. This is unlike in shallower waters, where a whale carcass will be consumed by scavengers over a relatively short period of time. Whale falls were first observed in the late 1970s with the development of deep-sea robotic exploration. Since then, several natural and experimental whale falls have been monitored through the use of observations from submersibles and remotely operated underwater vehicles ( ROVs) in order to understand patterns of ecological succession on the deep seafloor. Deep sea whale falls are thought to be hotspots of adaptive radiation for specialized fauna. Organisms that have been observed at deep-sea whale fall sites include octopus, giant isopods, squat lobsters, polychaetes, prawns, shrimp, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venenivibrio
''Venenivibrio stagnispumantis'' strain CP.B2 is the first microorganisms isolated from the terrestrial hot spring Champagne Pool (75 °C, pH 5.5) in Waiotapu, New Zealand. Morphology The cells are motile and slightly curved rods (1.04 to 1.56 µm long and 0.33 to 0.41 µm wide). Growth conditions The novel bacterium is an obligate chemolithotroph capable of utilizing H2 as electron donor, O2 as corresponding electron acceptor and CO2 as carbon source. ''Venenivibrio stagnispumantis'' gains metabolic energy using the "Knallgas" reaction H2 + ½ O2 → H2O. For growth either elemental sulphur (S0) or thiosulfate (S2O32−) is required. Growth is observed under thermophilic conditions between 45 °C and 75 °C (optimum 70 °C), under moderate acidophilic conditions between pH 4.8 and 5.8 (optimum pH 5.4) and under microaerophilic conditions between 1.0% and 10.0% (v/v) O2 (optimum between 4.0% and 8.0% (v/v) O2). Phylogeny Phylogenetic analysis ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Production
In ecology, the term productivity refers to the rate of generation of biomass in an ecosystem, usually expressed in units of mass per volume (unit surface) per unit of time, such as grams per square metre per day (g m−2 d−1). The unit of mass can relate to dry matter or to the mass of generated carbon. The productivity of autotrophs, such as plants, is called primary productivity, while the productivity of heterotrophs, such as animals, is called secondary productivity. Primary production Primary production is the synthesis of organic material from inorganic molecules. Primary production in most ecosystems is dominated by the process of photosynthesis, In which organisms synthesize organic molecules from sunlight, H2O, and CO2. Primary production is sometimes broken down into Net Primary Production (NPP) and Gross Primary Production (GPP). Gross primary production measures all carbon assimilated into organic molecules by primary producers. Net primary production measure ... [...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 life ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Fixation
Biological carbon fixation or сarbon assimilation is the process by which inorganic carbon (particularly in the form of carbon dioxide) is converted to organic compounds by living organisms. The compounds are then used to store energy and as structure for other biomolecules. Carbon is primarily fixed through photosynthesis, but some organisms use a process called chemosynthesis in the absence of sunlight. Organisms that grow by fixing carbon are called autotrophs, which include photoautotrophs (which use sunlight), and lithoautotrophs (which use inorganic oxidation). Heterotrophs are not themselves capable of carbon fixation but are able to grow by consuming the carbon fixed by autotrophs or other heterotrophs. "Fixed carbon", "reduced carbon", and "organic carbon" may all be used interchangeably to refer to various organic compounds. Chemosynthesis is carbon fixation driven by chemical energy, rather than from sunlight. Sulfur- and hydrogen-oxidizing bacteria often use the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Julian Chela-Flores
Julian Chela-Flores (born 13 June 1942) is a Venezuelan astrobiologist and physicist. He is known for his contributions to the field of planetary habitability. Biography His father, Raimundo Chela a mathematician of Lebanese family, encouraged his studies in science, while his mother raised his interest in the humanities. He lived in England where he studied in the University of London, obtaining a PhD in Quantum Mechanics in 1969. His field of research is astrobiology, in other words the science of the origin, evolution, distribution and destiny of life in the universe, especially life on Europa, the Jovian satellite. From 1971 till 1990 he worked in academic matters continually, especially in research at the Centre of Physics, the Venezuelan Institute for Scientific Research (Full Researcher 1978) and at the Physics Department, Simon Bolivar University (Full Professor 1980), both in Caracas. He is Full Professor ad honorem at the Institute for Advanced Studies (IDEA, Caraca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Europa (moon)
Europa , or Jupiter II, is the smallest of the four Galilean moons orbiting Jupiter, and the sixth-closest to the planet of all the 80 known moons of Jupiter. It is also the sixth-largest moon in the Solar System. Europa was discovered in 1610 by Galileo Galilei and was named after Europa, the Phoenician mother of King Minos of Crete and lover of Zeus (the Greek equivalent of the Roman god Jupiter). Slightly smaller than Earth's Moon, Europa is primarily made of silicate rock and has a water-ice crust and probably an iron–nickel core. It has a very thin atmosphere, composed primarily of oxygen. Its white-beige surface is striated by light tan cracks and streaks, but craters are relatively few. In addition to Earth-bound telescope observations, Europa has been examined by a succession of space-probe flybys, the first occurring in the early 1970s. In September 2022, the ''Juno'' spacecraft flew within about 200 miles of Europa for a more recent close-up view. Europa ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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