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Physonect
Physonectae is a suborder of siphonophores. In Japanese it is called (). Organisms in the suborder Physonectae follow the classic Siphonophore body plan. They are almost all pelagic, and are composed of a colony of specialized zooids that originate from the same fertilized egg. While Physonectae are not generally well-known by the public, a related species also of the order Siphonophorae is the Portuguese man o' war, well-known for its painful sting. Distribution The majority of physonect siphonophores are pelagic, with the exception of Rhodallidae, which are a family of benthic physonects first collected during the ''Challenger'' expedition and described by Ernst Haekel in his ''Challenger'' monograph. Physonects, and siphonophores in general, are known to be widely distributed globally, but are understudied. Few individuals have been collected and are often misidentified. As a result, their exact global distributions are unclear. Morphology All physonect siphonophor ...
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Siphonophore
Siphonophorae (from Greek ''siphōn'' 'tube' + ''pherein'' 'to bear') is an order within Hydrozoa, which is a class of marine organisms within the phylum Cnidaria. According to the World Register of Marine Species, the order contains 175 species thus far. Although a siphonophore may appear to be an individual organism, each specimen is in fact a colonial organism composed of medusoid and polypoid zooids that are morphologically and functionally specialized. Zooids are multicellular units that develop from a single fertilized egg and combine to create functional colonies able to reproduce, digest, float, maintain body positioning, and use jet propulsion to move. Most colonies are long, thin, transparent floaters living in the pelagic zone. Like other hydrozoans, some siphonophores emit light to attract and attack prey. While many sea animals produce blue and green bioluminescence, a siphonophore in the genus ''Erenna'' was only the second life form found to produce a red lig ...
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Siphonophorae
Siphonophorae (from Greek ''siphōn'' 'tube' + ''pherein'' 'to bear') is an order within Hydrozoa, which is a class of marine organisms within the phylum Cnidaria. According to the World Register of Marine Species, the order contains 175 species thus far. Although a siphonophore may appear to be an individual organism, each specimen is in fact a colonial organism composed of medusoid and polypoid zooids that are morphologically and functionally specialized. Zooids are multicellular units that develop from a single fertilized egg and combine to create functional colonies able to reproduce, digest, float, maintain body positioning, and use jet propulsion to move. Most colonies are long, thin, transparent floaters living in the pelagic zone. Like other hydrozoans, some siphonophores emit light to attract and attack prey. While many sea animals produce blue and green bioluminescence, a siphonophore in the genus ''Erenna'' was only the second life form found to produce a red li ...
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Fanny Moser (scientist)
Fanny Moser, also known as Fanny Hoppe-Moser, (27 May 1872 - 24 February 1953) was a Swiss-German zoologist. Her father Johan-Heinrich Moser was an engineer and built the Moser dam in Schaffhausen. In 1896 Fanny Moser became the first female student to register at the University of Freiburg, where she studied medicine. She then began studying zoology in Munich and received her doctorate in 1902, specialising in the developmental history of the vertebrate lung. In 1903 she married the composer Jaroslav Hoppe. They moved to Berlin and Moser began her international research, which included identifying nine new species, most notably the cold-water southern physonect '' Pyrostephos vanhoeffeni'' that was collected from the South Pole expedition for the Museum of Natural History in Berlin. The prince of Monaco commissioned her to work on his zoological deep sea collection. She became involved with parapsychology Parapsychology is the study of alleged psychic phenomena (extrasenso ...
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Japanese Language
is spoken natively by about 128 million people, primarily by Japanese people and primarily in Japan, the only country where it is the national language. Japanese belongs to the Japonic or Japanese- Ryukyuan language family. There have been many attempts to group the Japonic languages with other families such as the Ainu, Austroasiatic, Koreanic, and the now-discredited Altaic, but none of these proposals has gained widespread acceptance. Little is known of the language's prehistory, or when it first appeared in Japan. Chinese documents from the 3rd century AD recorded a few Japanese words, but substantial Old Japanese texts did not appear until the 8th century. From the Heian period (794–1185), there was a massive influx of Sino-Japanese vocabulary into the language, affecting the phonology of Early Middle Japanese. Late Middle Japanese (1185–1600) saw extensive grammatical changes and the first appearance of European loanwords. The basis of the standard dialect moved f ...
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Dioecious
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is biparental reproduction. Dioecy has costs, since only about half the population directly produces offspring. It is one method for excluding self-fertilization and promoting allogamy (outcrossing), and thus tends to reduce the expression of recessive deleterious mutations present in a population. Plants have several other methods of preventing self-fertilization including, for example, dichogamy, herkogamy, and self-incompatibility. Dioecy is a dimorphic sexual system, alongside gynodioecy and androdioecy. In zoology In zoology, dioecious species may be opposed to hermaphroditic species, meaning that an individual is either male or female, in which case the synonym gonochory is more often used. Most animal species are dioecious (gon ...
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Protandrous
Sequential hermaphroditism (called dichogamy in botany) is a type of hermaphroditism that occurs in many fish, gastropods, and plants. Sequential hermaphroditism occurs when the individual changes its sex at some point in its life. In particular, a sequential hermaphrodite produces eggs (female gametes) and sperm (male gametes) at different stages in life. Species that can undergo these changes from one sex to another do so as a normal event within their reproductive cycle that is usually cued by either social structure or the achievement of a certain age or size. In animals, the different types of change are male to female (protandry or protandrous hermaphroditism), female to male (protogyny or protogynous hermaphroditism), bidirectional (serial or bidirectional hermaphroditism). Both protogynous and protandrous hermaphroditism allow the organism to switch between functional male and functional female. Bidirectional hermaphrodites have the capacity for sex change in either directi ...
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Monoecy
Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system alongside gynomonoecy, andromonoecy and trimonoecy. Monoecy is connected to anemophily. It can prevent self-pollination in an individual flower but cannot prevent self-pollination between male and female flowers on the same plant. Monoecy in angiosperms has been of interest for evolutionary biologists since Charles Darwin. Terminology Monoecious comes from the Greek words for one house. History The term monoecy was first introduced in 1735 by Carl Linnaeus. Darwin noted that the flowers of monoecious species sometimes showed traces of the opposite sex function. Monoecious hemp was first reported in 1929. Occurrence Monoecy is most common in temperate climates and is often associated with inefficient pollinators or wind-pollinated plants. It may be beneficial to reducing pollen-stigma interferenc ...
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Gonophore
A gonophore is a reproductive organ in Hydrozoa that produces gametes. It is a sporosac, a medusa or any intermediate stage. The name is derived from the Greek words (, that which produces seed) and (, -bearing). Gonophores are borne on branching stalks that grow out as a ring from the hydranth (i.e. the hydroid polyp, bearing a mouth, digestive cavity and tentacles) wall. The germ cells are formed from the inner layer of the entocodon. The entocodon is the primordium (i.e. the first cells that give rise to the development of an organ) of the subumbrella (i.e. the concave oral surface of a medusa) in the development of medusae from the gonophore. The gonophores in the order Leptomedusae are borne on much reduced hydranths and are usually protected in a peridermal (i.e. belonging to a hydroid perisarc) gonotheca. Medusae forming on fully developed hydranths are extremely rare; usually the gonophores develop into medusae or into sessile sporosacs. The gonophores in the superfam ...
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