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Xenoturbella Japonica
''Xenoturbella japonica'' is a marine benthic worm-like species that belongs to the genus ''Xenoturbella''. It has been discovered in western Pacific Ocean by a group of Japanese scientists from the University of Tsukuba. The species was described in 2017 in a study published in the journal BMC Evolutionary Biology, and amended in 2018. ''Xenotrubella japonica'' is known for lacking respiratory, circulatory and an excretory system. Description The etymology of the species name corresponds to the locality where the specimens were sampled. ''Xenoturbella japonica'' is in length, with a pale orange colouration. The body wall displays ring and side furrows. The mouth is orientated ventrally, just anterior to the ring furrow. The live specimen exhibits a conspicuous ventral epidermal glandular network. Tissues contain exogenous DNA corresponding to bivalve mollusks, the vesicomyid '' Acila castrensis'' and '' Nucula nucleus''. Phylogeny Comparison of mitochondrial DNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenoturbella Bockii Longitudinal Section English
''Xenoturbella'' is a genus of very simple bilaterians up to a few centimeters long. It contains a small number of marine benthic worm-like species. The first known species (''Xenoturbella bocki'') was discovered in 1915 by Sixten Bock, but it was only properly described in 1949 by Einar Westblad. Description ''Xenoturbella'' has a very simple body plan. It consists of dorsoventrally flattened acoelomate animals, with an anterior circumferential furrow. It shows two ciliated epithelial layers: an external epidermis and an internal gastrodermis lining the simple sac-like gut. The multiciliated epiderm displays unique interconnected ciliary rootlets and mode of withdrawal and resorption of worn epidermal cells. The mouth is a mid-ventral pore leading to a gastral cavity, and there is no anus: waste is dispelled through the same opening as food is taken in. The nervous system is composed by a net of interconnected neurons beneath the epidermis, without any concentration of neuron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phys
Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events." Physics is one of the most fundamental scientific disciplines, with its main goal being to understand how the universe behaves. "Physics is one of the most fundamental of the sciences. Scientists of all disciplines use the ideas of physics, including chemists who study the structure of molecules, paleontologists who try to reconstruct how dinosaurs walked, and climatologists who study how human activities affect the atmosphere and oceans. Physics is also the foundation of all engineering and technology. No engineer could design a flat-screen TV, an interplanetary spacecraft, or even a better mousetrap without first understanding the basic laws of physics. (. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with the same cladogram. A cladogram uses lines that branch off in different directions ending at a clade, a group of organisms with a last common ancestor. There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit the traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other evolutionary narratives about ance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrial DNA
Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial DNA is only a small portion of the DNA in a eukaryotic cell; most of the DNA can be found in the cell nucleus and, in plants and algae, also in plastids such as chloroplasts. Human mitochondrial DNA was the first significant part of the human genome to be sequenced. This sequencing revealed that the human mtDNA includes 16,569 base pairs and encodes 13 proteins. Since animal mtDNA evolves faster than nuclear genetic markers, it represents a mainstay of phylogenetics and evolutionary biology. It also permits an examination of the relatedness of populations, and so has become important in anthropology and biogeography. Origin Nuclear and mitochondrial DNA are thought to be of separate evolutionary origin, with the mtDNA being derived ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucula
''Nucula'' is a genus of very small saltwater clams. They are part of the Family (biology), family Nuculidae. Fossil records This genus is very ancient. Fossils are known from the Arenig to the Quaternary (age range: from 478.6 to 0.0 million years ago). Fossils are found in the marine strata all over the world. Description Shells of species within this genus can reach a size of about . They are equivalve, symmetrical, approximately triangular. The surface has fine concentric growth lines. These clams live in the muddy sand close to the sediment surface at a depth of 20 to 200 meters. Species Nowadays there are still many species of this genus, which have had virtually no change in the course of time. Species within the genus ''Nucula'' include: * ''Nucula annulata'' Hampson, 1971 * ''Nucula atacellana'' Schenck, 1939 - cancellate nutclam * ''Nucula austrobenthalis'' Dell, 1990 * ''Nucula beachportensis'' Verco, 1907 * ''Nucula benguelana'' (A. H. Clarke, 1961) * ''Nucu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acila
''Acila'' is a genus of marine Bivalvia, bivalves in the family Nuculidae. ''Acila'' fossils have been found dating back to 113.0 Mega-annum, Ma ago. Species As of March, 2021, the genus contains the following species: *''Acila castrensis'' Hinds, 1843 *''Acila divaricata'' Hinds, 1843 *''Acila fultoni'' E. A. Smith, 1892 *''Acila granulata'' E. A. Smith, 1906 *''Acila insignis'' Gould, 1861 *''Acila jucunda'' Thiele, 1931 *''Acila minutoides'' Kuroda & Habe in Habe, 1958 *''Acila mirabilis'' A. Adams & Reeve, 1850 *''Acila vigilia'' Schenck, 1936 References [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vesicomyidae
Vesicomyidae is a family of saltwater clams, marine bivalve molluscs in the superfamily Glossoidea. MolluscaBase eds. (2022). MolluscaBase. Vesicomyidae Dall & Simpson, 1901. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=23140 on 2022-02-01 Genera and species Genera, and some selected species, within the family Vesicomyidae are: ; Subfamily Pliocardiinae Woodring, 1925 * '' Abyssogena'' Krylova, Sahling & R. Janssen, 2010 * '' Archivesica'' Dall, 1908 * '' Austrogena'' Krylova, Sellanes, F. Valdés & D'Elía, 2014 * '' Callogonia'' Dall, 1889 * ''Calyptogena'' Dall, 1891 ** ''Calyptogena magnifica'' ** ''Calyptogena pacifica'' Dall, 1891 * '' Christineconcha'' Krylova & Cosel, 2011 * † '' Cytherocardia'' Sacco, 1900 * '' Ectenagena'' Woodring, 1938 * '' Elenaconcha'' Cosel & Olu, 2009 * † '' Hubertschenckia'' Takeda, 1953 * '' Isorropodon'' Sturany, 1896 * '' Laubiericoncha'' von Cosel & Olu, 2008 ** '' Lau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalve
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bivalves have no head and they lack some usual molluscan organs, like the radula and the odontophore. They include the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment, where they are relatively safe from predation. Others lie on the sea floor or attach themselves to rocks or other hard surfaces. Some bivalves, such as the scallops and file shells, can swim. The shipworms bore into wood, clay, or stone and live inside these substances. The shell of a bivalve is composed of calc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exogenous DNA
Exogenous DNA is DNA originating outside the organism of concern or study. Exogenous DNA can be found naturally in the form of partially degraded fragments left over from dead cells. These DNA fragments may then become integrated into the chromosomes of nearby bacterial cells to undergo mutagenesis. This process of altering bacteria is known as Transformation (genetics), transformation. Bacteria may also undergo artificial transformation through chemical and biological processes. The introduction of exogenous DNA into eukaryotic cells is known as transfection. Exogenous DNA can also be artificially inserted into the genome, which revolutionized the process of genetic modification in animals. By microinjecting an artificial transgene into the nucleus of an animal embryo, the exogenous DNA is allowed to merge the cell's existing DNA to create a genetically modified, transgenic animal. The creation of transgenic animals also leads into the study of altering sperm cells with exogenous D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etymology
Etymology ()The New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time". is the study of the history of the Phonological change, form of words and, by extension, the origin and evolution of their semantic meaning across time. It is a subfield of historical linguistics, and draws upon comparative semantics, Morphology_(linguistics), morphology, semiotics, and phonetics. For languages with a long recorded history, written history, etymologists make use of texts, and texts about the language, to gather knowledge about how words were used during earlier periods, how they developed in Semantics, meaning and Phonological change, form, or when and how they Loanword, entered the language. Etymologists also apply the methods of comparative linguistics to reconstruct information about forms that are too old for any direct information to be available. By analyzing related ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Business Times
The ''International Business Times'' is an American online news publication that publishes five national editions in four languages. The publication, sometimes called ''IBTimes'' or ''IBT'', offers news, opinion and editorial commentary on business and commerce. IBT is one of the world's largest online news sources, receiving forty million unique visitors each month. Its 2013 revenues were around $21 million. As of January 2022, IBTimes editions include Australia, India, International, Singapore, U.K. and U.S. ''IBTimes'' was launched in 2005; it is owned by IBT Media, and was founded by Etienne Uzac and Johnathan Davis. Its headquarters are in the Financial District of Lower Manhattan, New York City. History Founder Etienne Uzac, a native of France, came up with the idea for the global business news site while a student at the London School of Economics. He found that the strongest business newspapers had a focus on the United States and Europe and planned to provide broad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benthos
Benthos (), also known as benthon, is the community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone.Benthos from the Census of Antarctic Marine Life website This community lives in or near marine or freshwater sedimentary environments, from s along the , out to the , and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
