|
Trochophore
A trochophore () 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 in order to capture it more easily. Occurrence Trochophores exist as a larval form within the trochozoan clade, which include the entoprocta, entoprocts, molluscs, annelids (including echiurans and 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] |
Metatrochophore
A metatrochophore (;) is a type of larva developed from the trochophore larva of a polychaete annelid. The metatrochophore of a deep-sea hydrothermal vent vestimentiferan has a foregut and a midgut. The foregut cells have several microvilli, basal bodies, and cilia, with e-dense granules dispersed in the apical cell region. The diameter of the midgut in one specimen was 50 μm and the lumen’s diameter was 7 μm, in which the cilia extended and e-dense material was found. The midgut cells had fewer cilia than the fore- and hindgut cells but exhibited an extensive, e-dense brush of microvilli and a nucleus in the apical third of the cell body. Additionally, the midgut contained a few bacteria in the lumen. Metatrochophores have a number of features trochophores lack, including eyespots and Segmentation_(biology), segments. References Larvae Annelids {{developmental-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entoprocta
Entoprocta (), or Kamptozoa , is a phylum (biology), phylum of mostly Sessility (zoology), sessile aquatic animals, ranging from long. Mature individuals are goblet-shaped, on relatively long stalks. They have a "crown" of solid tentacles whose cilia generate water currents that filter feeder, draw food particles towards the mouth, and both the mouth and anus lie inside the "crown". The superficially similar Bryozoa (Ectoprocta) have the anus outside a "crown" of hollow tentacles. Most family (biology), families of entoprocts are colonial, and all but 2 of the 150 species are marine. A few solitary species can move slowly. Some species eject unfertilized ovum, ova into the water, while others keep their ova in brood chambers until they hatch, and some of these species use placenta-like organs to nourish the developing eggs. After hatching, the larvae swim for a short time and then settle on a surface. There they Metamorphosis, metamorphose, and the larval gut rotates by up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollusc
Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The number of additional fossil species is estimated between 60,000 and 100,000, and the proportion of undescribed species is very high. Many taxa remain poorly studied. Molluscs are the largest marine biology, marine phylum, comprising about 23% of all the named marine organisms. They are highly diverse, not just in size and anatomical structure, but also in behaviour and habitat, as numerous groups are freshwater mollusc, freshwater and even terrestrial molluscs, terrestrial species. The phylum is typically divided into 7 or 8 taxonomy (biology), taxonomic class (biology), classes, of which two are entirely extinct. Cephalopod molluscs, such as squid, cuttlefish, and octopuses, are among the most neurobiology, neurologi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annelid
The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments. The annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion. Most textbooks still use the traditional division into polychaetes (almost all marine), oligochaetes (which include earthworms) and leech-like species. Cladistic research since 1997 has radically changed this scheme, viewing leeches as a sub-group of oligochaetes and oligochaetes as a sub-group of polychaetes. In addition, the Pogonophora, Echiura and Sipuncula, previously regarded as separate phyla, are now regarded as sub-grou ... [...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, and brachiopods. 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 or placed in the ... [...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 Māori name for three species in New Zealand is pāua. Description The shells of abalone 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 abal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serpulidae
The Serpulidae are a family of sessile, tube-building annelid worms in the class Polychaeta. The members of this family differ from other sabellid tube worms in that they have a specialized 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 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 late Permian), and possibly the upper Permian south China 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 serpulid shells can sometimes be confused with the shells of a family of marine gastropo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pomatoceros Lamarckii
''Pomatoceros lamarckii'' is a species of tube-building annelid The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to vario ... 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 investigation. Refe ... [...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 The Serpulidae are a family of sessile, tube-building annelid worms in the class Polychaeta. The members of this family differ from other sabellid tube worms in that they have a specialized operculum that blocks the entrance of their tubes w .... Species The species in the genusWorld Register of Marine Species include: * '' Spirobranchus aloni'' Perry, et. al. 2018 * '' Spirobranchus corniculatus'' Grube, 1862 * '' Spirobranchus latiscapus'' Marenzeller, 1885 * '' Spirobranchus americanus'' Day, 1973 * '' Spirobranchus arabicus'' Monro, 1937 * '' Spirobranchus baileybrockae'' Pillai. 2009 * '' Spirobranchus cariniferus'' Gray, 1843 * '' Spirobranchus coronatus'' Straughan, 1967 * '' Spirobranchus corrugatus'' Straughan, 1967 * '' Spirobranchus decoratus'' Imajima, 1982 * '' Spirobranchus dendropoma ... [...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 classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek Dark Ages, Dark Ages (), the Archaic Greece, Archaic or Homeric Greek, Homeric period (), and the Classical Greece, Classical period (). Ancient Greek was the language of Homer and of fifth-century Athens, fifth-century Athenian historians, playwrights, and Ancient Greek philosophy, 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 Homeric Greek, Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period (), Ancient Greek was followed by Koine Greek, which is regar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
