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Xenoturbella Churro
''Xenoturbella churro'' is a marine, benthic, deep-water worm-like species that belongs to the genus ''Xenoturbella''. It was discovered in eastern Pacific Ocean by a group of Californian and Australian scientists. The species was described in 2016 from a single specimen. ''X. churro'' shares morphological similarities with other species of the genus ''Xenoturbella'', and is known for lacking respiratory, circulatory and an excretory system. Description The etymology of the species name refers to the resemblance with churro, a fried-dough pastry. This animal is in length, with a uniform orange/pink colouration. The body wall displays several furrows: on the circumference, on the side, and four deep, longitudinal, dorsal ones. The longitudinal orientation involves a rounded anterior end, while the posterior end sharply reduces in thickness. The mouth is orientated ventrally, halfway between the anterior end and the ring furrow. The live specimen exhibited an epidermal v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. ''Xenoturbella japonica'' is known for lacking respiratory, circulatory and excretory systems. 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] |
Churro
A churro (, ) is a type of fried dough from Spanish and Portuguese cuisine, made with choux pastry dough piped into hot oil with a piping bag and large closed star tip or similar shape. They are also found in Latin American cuisine, Philippine cuisine and in other areas that have received immigration from Spanish and Portuguese-speaking countries, especially in France and the Southwestern United States. In Spain, churros can either be thin (and sometimes knotted) or long and thick, where they are known as ''porras'', ''jeringos'', or ''tejeringos'' in some regions. They are normally eaten for breakfast dipped in coffee, or in hot chocolate for an afternoon snack. There are also two slightly different snacks in Portugal, called ''porra'' and fartura, which are filled with jelly instead of the '' doce de leite'' traditional to Brazilian churros. History The origin of churros is unclear. But according to food historian Michael Krondl, "today's churro is not that different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrial DNA
Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in a eukaryotic cell; most of the DNA is in the cell nucleus, and, in plants and algae, the DNA also is found in plastids, such as chloroplasts. Mitochondrial DNA is responsible for coding of 13 essential subunits of the complex oxidative phosphorylation (OXPHOS) system which has a role in cellular energy conversion. Human mitochondrial DNA was the first significant part of the human genome to be sequenced. This sequencing revealed that human mtDNA has 16,569 base pairs and encodes 13 proteins. As in other vertebrates, the human mitochondrial genetic code differs slightly from nuclear DNA. Since animal mtDNA evolves faster than nuclear genetic markers, it represents a mainstay of phylogenetics and evolutionary biology. It als ... [...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 ** '' L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalve
Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed by a calcified exoskeleton consisting of a hinged pair of half-bivalve shell, shells known as valve (mollusc), valves. As a group, bivalves have no head and lack some typical molluscan organs such as the radula and the odontophore. Their gills have evolved into ctenidium (mollusc), ctenidia, specialised organs for feeding and breathing. Common bivalves include clams, oysters, Cockle (bivalve), cockles, mussels, scallops, and numerous other family (biology), families that live in saltwater, as well as a number of families that live in freshwater. Majority of the class are benthic filter feeders that bury themselves in sediment, where they are relatively safe from predation. Others lie on the sea floor or attach themselves to rocks or other h ... [...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. 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 DNA. History In 1928, ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamete
A gamete ( ) is a Ploidy#Haploid and monoploid, haploid cell that fuses with another haploid cell during fertilization in organisms that Sexual reproduction, reproduce sexually. Gametes are an organism's reproductive cells, also referred to as sex cells. The name gamete was introduced by the German cytologist Eduard Strasburger in 1878. Gametes of both mating individuals can be the same size and shape, a condition known as isogamy. By contrast, in the majority of species, the gametes are of different sizes, a condition known as anisogamy or heterogamy that applies to humans and other mammals. The human ovum has approximately 100,000 times the volume of a single human sperm cell. The type of gamete an organism produces determines its sex and sets the basis for the sexual roles and sexual selection. In humans and other species that produce two Morphology (biology), morphologically distinct types of gametes, and in which Gonochorism, each individual produces only one type, a femal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomical Terms Of Location
Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and axes. The meaning of terms that are used can change depending on whether a vertebrate is a biped or a quadruped, due to the difference in the neuraxis, or if an invertebrate is a non-bilaterian. A non-bilaterian has no anterior or posterior surface for example but can still have a descriptor used such as proximal or distal in relation to a body part that is nearest to, or furthest from its middle. International organisations have determined vocabularies that are often used as standards for subdisciplines of anatomy. For example, '' Termi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etymology
Etymology ( ) is the study of the origin and evolution of words—including their constituent units of sound and meaning—across time. In the 21st century a subfield within linguistics, etymology has become a more rigorously scientific study. Most directly tied to historical linguistics, philology, and semiotics, it additionally draws upon comparative semantics, morphology, pragmatics, and phonetics in order to attempt a comprehensive and chronological catalogue of all meanings and changes that a word (and its related parts) carries throughout its history. The origin of any particular word is also known as its ''etymology''. For languages with a long written history, etymologists make use of texts, particularly texts about the language itself, to gather knowledge about how words were used during earlier periods, how they developed in meaning and form, or when and how they entered the language. Etymologists also apply the methods of comparative linguistics to reconstruct in ... [...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 collected in 1878 and 1879 in the Gullmar fiord on the Swedish west coast by August Malm and is stored in the collection of the Gothenburg Natural History Museum. A specimen is on display in the exhibition. It was collected again in the Gullmar fiord in 1915 by Sixten Bock, but it was only properly described in 1949 by Einar Westblad. The type specimens are kept at the Swedish Museum of Natural History in Stockholm. Description ''Xenoturbella'' has a very simple body plan. It consists of a dorsoventrally flattened acoelomate body, with a ventral furrow on each side running down from the anterior tip till they are stopped by an anterior circumferential furrow. It shows two ciliated epithelial layers: an external epidermis and an internal gastrodermis lining the simple sac-like g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Excretory System
The excretory system is a passive biological system that removes excess, unnecessary materials from the body fluids of an organism, so as to help maintain internal chemical homeostasis and prevent damage to the body. The dual function of excretory systems is the elimination of the waste products of metabolism and to drain the body of used up and broken down components in a liquid and gaseous state. In humans and other amniotes (mammals, birds and reptiles), most of these substances leave the body as urine and to some degree exhalation, mammals also expel them through sweating. Only the organs specifically used for the excretion are considered a part of the excretory system. In the narrow sense, the term refers to the urinary system. However, as excretion involves several functions that are only superficially related, it is not usually used in more formal classifications of anatomy or function. As most healthy functioning organs produce metabolic and other wastes, the entire o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circulatory System
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek meaning ''heart'', and Latin meaning ''vessels''). The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit. Some sources use the terms ''cardiovascular system'' and ''vascular system'' interchangeably with ''circulatory system''. The network of blood vessels are the great vessels of the heart including large elastic arteries, and large veins; other arteries, smaller arterioles, capillaries that join with venules (small veins), and other veins. The circulatory system is closed in vertebrates, which means that the blood never leaves the network of blood vessels. Many invertebrates such as arthropods have an open circulatory system with a he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
