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Australostichopus
''Australostichopus'' is a genus of sea cucumbers in the family Stichopodidae. It is monotypic, being represented by the single species ''Australostichopus mollis'',Moraes,G., Norhcote, P.C., Kalinin,V.I. ,Avilov, S.A., Silchenko,A.S., Dmitrenok, P.S. 2004. Structure of the major triterpene glycoside from the sea cucumber ''Stichopus mollis'' and evidence to reclassify this species into the new genus ''Australostichopus''. Biochemical Systematics and Ecology. 32 (7): 637–650. commonly known as the brown sea cucumber or Australasian sea cucumber. This species has stimulated interest for its fishery potential in the Southern Hemisphere,Stenton-Dozey, J. and Heath, P. 2009. A first for New Zealand: culturing our endemic sea cucumber for overseas markets. Water & Atmosphere .17(1). and for its capability to reduce waste produced by aquaculture. Despite its ecological role and abundance in New Zealand coastal waters, the scarcity of knowledge regarding ''A. mollis'' biology and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australostichopus Mollis Southern Sea Cucumber P2143491
''Australostichopus'' is a genus of sea cucumbers in the family Stichopodidae. It is monotypic, being represented by the single species ''Australostichopus mollis'',Moraes,G., Norhcote, P.C., Kalinin,V.I. ,Avilov, S.A., Silchenko,A.S., Dmitrenok, P.S. 2004. Structure of the major triterpene glycoside from the sea cucumber ''Stichopus mollis'' and evidence to reclassify this species into the new genus ''Australostichopus''. Biochemical Systematics and Ecology. 32 (7): 637–650. commonly known as the brown sea cucumber or Australasian sea cucumber. This species has stimulated interest for its fishery potential in the Southern Hemisphere,Stenton-Dozey, J. and Heath, P. 2009. A first for New Zealand: culturing our endemic sea cucumber for overseas markets. Water & Atmosphere .17(1). and for its capability to reduce waste produced by aquaculture. Despite its ecological role and abundance in New Zealand coastal waters, the scarcity of knowledge regarding ''A. mollis'' biology and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stichopodidae
The Stichopodidae are a family of sea cucumbers, part of the order Synallactida. Description Members of this family are mostly large or medium-sized holothuroids with a squarish cross-section, a flat ventral surface, and large, fleshy, cone-shaped projections. Their mouths are surrounded by 20 peltate tentacles. They are usually found on soft substrates, such as sand or rubble. Genera List of genera according to the World Register of Marine Species: * genus '' Apostichopus'' Liao, 1980 (8 species, North Pacific) * genus '' Astichopus'' Clark, 1922 (1 species, Caribbean) * genus '' Australostichopus'' Levin in Moraes et al., 2004 (1 species, New Zealand and southern Australia) * genus '' Eostichopus'' Cutress & Miller, 1982 (1 species, Caribbean) * genus '' Isostichopus'' Deichmann, 1958 (3 species, warm East Pacific and Atlantic) * genus '' Neostichopus'' Deichmann, 1948 (1 species, South Africa) * genus '' Parastichopus'' Clark, 1922 (2 species, Atlantic and North Pacific) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederick Hutton (scientist)
Captain Frederick Wollaston Hutton (16 November 1836 – 27 October 1905) was an English-New Zealand scientist who applied the theory of natural selection to explain the origins and nature of the natural history of New Zealand. An army officer in early life, he then had an academic career in geology and biology. He became one of the most able and prolific nineteenth century naturalists of New Zealand. Biography Hutton was born in Gate Burton, Lincolnshire, England, the son of the Rev. Henry Frederick Hutton and his wife Louisa Wollaston, daughter of the Rev. Henry John Wollaston. He passed through Southwell grammar school and the Naval Academy at Gosport, Hampshire. He studied applied science at King's College London before being commissioned in the Royal Welch Fusiliers and fighting in the Crimean War and the Indian Mutiny. Hutton returned to England in 1860, and continued to study geology at Sandhurst, being elected to the Geological Society of London in the same ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regeneration (biology)
In biology, regeneration is the process of renewal, restoration, and tissue growth that makes genomes, cells, organisms, and ecosystems resilient to natural fluctuations or events that cause disturbance or damage. Every species is capable of regeneration, from bacteria to humans. Regeneration can either be complete where the new tissue is the same as the lost tissue, or incomplete where after the necrotic tissue comes fibrosis. At its most elementary level, regeneration is mediated by the molecular processes of gene regulation and involves the cellular processes of cell proliferation, morphogenesis and cell differentiation. Regeneration in biology, however, mainly refers to the morphogenic processes that characterize the phenotypic plasticity of traits allowing multi-cellular organisms to repair and maintain the integrity of their physiological and morphological states. Above the genetic level, regeneration is fundamentally regulated by asexual cellular processes. Regeneration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holothurians
Sea cucumbers are echinoderms from the class Holothuroidea (). They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on the sea floor worldwide. The number of holothurian () species worldwide is about 1,717, with the greatest number being in the Asia-Pacific region. Many of these are gathered for human consumption and some species are cultivated in aquaculture systems. The harvested product is variously referred to as '' trepang'', ''namako'', ''bêche-de-mer'', or ''balate''. Sea cucumbers serve a useful role in the marine ecosystem as they help recycle nutrients, breaking down detritus and other organic matter, after which bacteria can continue the decomposition process. Like all echinoderms, sea cucumbers have an endoskeleton just below the skin, calcified structures that are usually reduced to isolated microscopic ossicles (or sclerietes) joined by connective tissue. In some species these can sometimes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reproductive Season
Seasonal breeders are animal species that successfully mate only during certain times of the year. These times of year allow for the optimization of survival of young due to factors such as ambient temperature, food and water availability, and changes in the predation behaviors of other species. Related sexual interest and behaviors are expressed and accepted only during this period. Female seasonal breeders will have one or more estrus cycles only when she is "in season" or fertile and receptive to mating. At other times of the year, they will be anestrus, or have a dearth of their sexual cycle. Unlike reproductive cyclicity, seasonality is described in both males and females. Male seasonal breeders may exhibit changes in testosterone levels, testes weight, and fertility depending on the time of year. Seasonal breeders are distinct from opportunistic breeders, that mate whenever the conditions of their environment become favorable, and continuous breeders that mate year-round. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumen (anatomy)
In biology, a lumen (plural lumina) is the inside space of a tubular structure, such as an artery or intestine. It comes . It can refer to: *The interior of a vessel, such as the central space in an artery, vein or capillary through which blood flows. *The interior of the gastrointestinal tract *The pathways of the bronchi in the lungs *The interior of renal tubules and urinary collecting ducts *The pathways of the female genital tract, starting with a single pathway of the vagina, splitting up in two lumina in the uterus, both of which continue through the Fallopian tubes In cell biology, a lumen is a membrane-defined space that is found inside several organelles, cellular components, or structures: *thylakoid, endoplasmic reticulum, Golgi apparatus, lysosome, mitochondrion, or microtubule Transluminal procedures ''Transluminal procedures'' are procedures occurring through lumina, including: *Natural orifice transluminal endoscopic surgery in the lumina of, for example, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermatozoa
A spermatozoon (; also spelled spermatozoön; ; ) is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote. (A zygote is a single cell, with a complete set of chromosomes, that normally develops into an embryo.) Sperm cells contribute approximately half of the nuclear genetic information to the diploid offspring (excluding, in most cases, mitochondrial DNA). In mammals, the sex of the offspring is determined by the sperm cell: a spermatozoon bearing an X chromosome will lead to a female (XX) offspring, while one bearing a Y chromosome will lead to a male (XY) offspring. Sperm cells were first observed in Antonie van Leeuwenhoek's laboratory in 1677. Mammalian spermatozoon structure, function, and size Humans The human sperm cell is the reproductive cell in males and will only survive in warm environments; once it leaves the male body the sperm's survival likelihood is reduced and it may die, thereby ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oocyte
An oocyte (, ), oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell (PGC), which then undergoes mitosis, forming oogonia. During oogenesis, the oogonia become primary oocytes. An oocyte is a form of genetic material that can be collected for cryoconservation. Formation The formation of an oocyte is called oocytogenesis, which is a part of oogenesis. Oogenesis results in the formation of both primary oocytes during fetal period, and of secondary oocytes after it as part of ovulation. Characteristics Cytoplasm Oocytes are rich in cytoplasm, which contains yolk granules to nourish the cell early in development. Nucleus During the primary oocyte stage of oogenesis, the nucleus is called a germinal vesicle. The only normal human type of secondary oocyte has t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonad
A gonad, sex gland, or reproductive gland is a mixed gland that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. The male gonad, the testicle, produces sperm in the form of spermatozoa. The female gonad, the ovary, produces egg cells. Both of these gametes are haploid cells. Some hermaphroditic animals have a type of gonad called an ovotestis. Evolution It is hard to find a common origin for gonads, but gonads most likely evolved independently several times. Regulation The gonads are controlled by luteinizing hormone and follicle-stimulating hormone, produced and secreted by gonadotropes or gonadotrophins in the anterior pituitary gland. This secretion is regulated by gonadotropin-releasing hormone produced in the hypothalamus. Development Gonads start developing as a common primordium (an organ in the earliest stage of development), in the form of genital ridges, which are only l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spawning
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquatic mammals and reptiles, reproduce through the process of spawning. Spawn consists of the reproductive cells (gametes) of many aquatic animals, some of which will become fertilized and produce offspring. The process of spawning typically involves females releasing ova (unfertilized eggs) into the water, often in large quantities, while males simultaneously or sequentially release spermatozoa (milt) to fertilize the eggs. Most fish reproduce by spawning, as do most other aquatic animals, including crustaceans such as crabs and shrimps, molluscs such as oysters and squid, echinoderms such as sea urchins and sea cucumbers, amphibians such as frogs and newts, aquatic insects such as mayflies and mosquitoes and corals, which are actually small ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reproductive Season
Seasonal breeders are animal species that successfully mate only during certain times of the year. These times of year allow for the optimization of survival of young due to factors such as ambient temperature, food and water availability, and changes in the predation behaviors of other species. Related sexual interest and behaviors are expressed and accepted only during this period. Female seasonal breeders will have one or more estrus cycles only when she is "in season" or fertile and receptive to mating. At other times of the year, they will be anestrus, or have a dearth of their sexual cycle. Unlike reproductive cyclicity, seasonality is described in both males and females. Male seasonal breeders may exhibit changes in testosterone levels, testes weight, and fertility depending on the time of year. Seasonal breeders are distinct from opportunistic breeders, that mate whenever the conditions of their environment become favorable, and continuous breeders that mate year-round. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
