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Trocophore
A trochophore (; also spelled trocophore) is a type of free-swimming planktonic marine larva with several bands of cilia. By moving their cilia rapidly, they make a water eddy, to control their movement, and to bring their food closer, to capture it more easily. Occurrence Trochophores exist as a larval form within the trochozoan clade, which include the entoprocts, molluscs, annelids, echiurans, sipunculans and nemerteans. Together, these phyla make up part of the Lophotrochozoa; it is possible that trochophore larvae were present in the life cycle of the group's common ancestor. Etymology The term ''trochophore'' derives from the ancient Greek (), meaning "wheel", and () — or () —, meaning 'to bear, to carry', because the larva is bearing a wheel-shaped band of cilia. Feeding habits Trochophore larvae are often planktotrophic; that is, they feed on other plankton species. Life cycle The example of the development of the annelid ''Pomatoceros lamarckii'' ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nemertea
Nemertea is a phylum of animals also known as ribbon worms or proboscis worms, consisting of 1300 known species. Most ribbon worms are very slim, usually only a few millimeters wide, although a few have relatively short but wide bodies. Many have patterns of yellow, orange, red and green coloration. The foregut, stomach and intestine run a little below the midline of the body, the anus is at the tip of the tail, and the mouth is under the front. A little above the gut is the rhynchocoel, a cavity which mostly runs above the midline and ends a little short of the rear of the body. All species have a proboscis which lies in the rhynchocoel when inactive but everts to emerge just above the mouth to capture the animal's prey with venom. A highly extensible muscle in the back of the rhynchocoel pulls the proboscis in when an attack ends. A few species with stubby bodies filter feed and have suckers at the front and back ends, with which they attach to a host. The brain is a rin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haliotis Asinina Trochophore
''Haliotis'', common name abalone, is the only genus in the family Haliotidae. This genus once contained six subgenera. These subgenera have become alternate representations of ''Haliotis''. The genus consists of small to very large, edible, herbivorous sea snails, marine gastropod molluscs. The number of species recognized worldwide ranges between 30 and 130, with over 230 species-level taxa described. The most comprehensive treatment of the family considers 56 species valid, with 18 additional subspecies. Other common names are ear shells, sea ears, and, rarely, muttonfish or muttonshells in parts of Australia, ormer in the UK, perlemoen in South Africa, and the Maori name for three species in New Zealand is pāua. Description The shells of abalones have a low, open, spiral structure, and are characterized by having several open respiratory pores in a row near the shell's outer edge. The thick inner layer of the shell is composed of nacre, which in many species of abalone i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metatrochophore
A metatrochophore (;) is a type of larva developed from the trochophore larva of a polychaete annelid The annelids (Annelida , from Latin ', "little ring"), also known as the segmented worms, are a large phylum, with over 22,000 extant species including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecol .... Metatrochophores have a number of features trochophores lack, including eyespots and segments. References Larvae Annelids {{developmental-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serpulidae
The Serpulidae are a family (biology), family of Sessility (zoology), sessile, tube worm (body plan), tube-building annelid worms in the class Polychaeta. The members of this family differ from other Sabellidae, sabellid tube worms in that they have a specialized Operculum (animal), operculum that blocks the entrance of their tubes when they withdraw into the tubes. In addition, serpulids secrete tubes of calcium carbonate. Serpulids are the most important biomineralising polychaetes, biomineralizers among annelids. About 300 species in the family Serpulidae are known, all but one of which live in saline waters. The earliest serpulids are known from the Permian (Wordian to lopingian, late Permian). The blood of most species of serpulid and sabellid worms contains the oxygen-binding pigment chlorocruorin. This is used to transport oxygen to the tissues. It has an affinity for carbon monoxide which is 570 times as strong as that of the haemoglobin found in human blood. Empty serpul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pomatoceros Lamarckii
''Pomatoceros lamarckii'' is a species of tube-building annelid worms which is widespread in intertidal and sub-littoral zones around the United Kingdom and northern Europe. They are found attached to firm substrates, from rocks to animal shells to man made structures, and often are noted for their detrimental effect on shipping. It is closely related to, and often confused with, ''Pomatoceros triqueter''. ''Pomatoceros lamarckii'' has been the subject of a number of scientific investigations, due to its presence near sites of historic scientific study, relatively underived mode of development and slowly evolving genetic complement. Recently this organism has been the subject of in depth transcriptomic Transcriptomics technologies are the techniques used to study an organism's transcriptome, the sum of all of its RNA transcripts. The information content of an organism is recorded in the DNA of its genome and expressed through transcription. He ... investigation. Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pomatoceros Lamarckii Development
''Spirobranchus'' is a small genus of tube-building annelid fanworms in the family Serpulidae. Species The species in the genusWorld Register of Marine Species include: * ''Spirobranchus giganteus'' Pallas Pallas may refer to: Astronomy * 2 Pallas asteroid ** Pallas family, a group of asteroids that includes 2 Pallas * Pallas (crater), a crater on Earth's moon Mythology * Pallas (Giant), a son of Uranus and Gaia, killed and flayed by Athena * Pall ..., 1766. Christmas-tree worm * ''Spirobranchus corniculatus'' (Grube, 1862) * ''Spirobranchus latiscapus'' Marenzeller, 1885 * ''Spirobranchus aloni'' Perry, Bronstein, Simon-Blecher, Atkins, Kupriyanova, ten Hove, Levy & Fine, 2018 * ''Spirobranchus americanus'' (Day, 1973) * ''Spirobranchus arabicus'' Monro, 1937 * ''Spirobranchus baileybrockae'' Pillai. 2009 * '' Spirobranchus cariniferus'' (Gray, 1843) * ''Spirobranchus coronatus'' Straughan, 1967 * ''Spirobranchus corr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic period (), and the Classical period (). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers. It has contributed many words to English vocabulary and has been a standard subject of study in educational institutions of the Western world since the Renaissance. This article primarily contains information about the Epic and Classical periods of the language. From the Hellenistic period (), Ancient Greek was followed by Koine Greek, which is regarded as a separate historical stage, although its earliest form closely resembles Attic Greek and its latest form approaches Medieval Greek. There were several regional dialects of Ancient Greek, of which Attic Greek developed into Koine. Dia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lophotrochozoa
Lophotrochozoa (, "crest/wheel animals") is a clade of protostome animals within the Spiralia. The taxon was established as a monophyletic group based on molecular evidence. The clade includes animals like annelids, molluscs, bryozoans, brachiopods, and platyhelminthes. Groups Lophotrochozoa was defined in 1995 as the "last common ancestor of the three traditional lophophorate taxa (brachiopods, bryozoans, and phoronid worms), the mollusks and the annelids, and all of the descendants of that common ancestor". It is a cladistic definition (a node-based name), so the affiliation to Lophotrochozoa of spiralian groups not mentioned directly in the definition depends on the topology of the spiralian tree of life, and in some phylogenetic hypotheses, Lophotrochozoa may even be synonymous to Spiralia. Nemertea and Orthonectida (if not directly considered as part of Annelida) are probably lophotrochozoan phyla; Dicyemida, Gastrotricha, and Platyhelminthes may be lophotrochozoans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sipuncula
The Sipuncula or Sipunculida (common names sipunculid worms or peanut worms) is a class containing about 162 species of unsegmented marine annelid worms. The name ''Sipuncula'' is from the genus name ''Sipunculus'', and comes from the Latin ''siphunculus'' meaning a "small tube". Sipuncula was once considered a phylum, but was demoted to a class of Annelida, based on recent molecular work. Sipunculans vary in size but most species are under in length. The body is divided into an unsegmented, bulbous trunk and a narrower, anterior section, called the "introvert", which can be retracted into the trunk. The mouth is at the tip of the introvert and is surrounded in most groups by a ring of short tentacles. With no hard parts, the body is flexible and mobile. Although found in a range of habitats throughout the world's oceans, the majority of species live in shallow water habitats, burrowing under the surface of sandy and muddy substrates. Others live under stones, in rock crevic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lexico
Lexico was a dictionary website that provided a collection of English and Spanish dictionaries produced by Oxford University Press (OUP), the publishing house of the University of Oxford. While the dictionary content on Lexico came from OUP, this website was operated by Dictionary.com, whose eponymous website hosts dictionaries by other publishers such as Random House. The website was closed and redirected to Dictionary.com on 26 August 2022. Before the Lexico site was launched, the '' Oxford Dictionary of English'' and ''New Oxford American Dictionary'' were hosted by OUP's own website Oxford Dictionaries Online (ODO), later known as Oxford Living Dictionaries. The dictionaries' definitions have also appeared in Google definition search and the Dictionary application on macOS, among others, licensed through the Oxford Dictionaries API. History In the 2000s, OUP allowed access to content of the ''Compact Oxford English Dictionary of Current English'' on a website called AskOx ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
