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Chimaericola Leptogaster
''Chimaericola leptogaster'' is a species of polyopisthocotylean monogenean in the family Chimaericolidae. It is ectoparasitic on the gills of the chimaera ''Chimaera monstrosa''. History According to Brinkmann,Brinkmann Jr, A. (1942). On ''Octobothrium leptogaster'' FS Leuckart. Goteborgs Kungliga Vetenskaps-och Vitterhets-Samhalles Handlingar. Series B, 2(3), 1-29. the species was discovered as early as 1828 on the gills of chimaeras off Norway by Rapp and was given a scientific name by Friedrich Sigismund Leuckart in 1830, as ''Octobothrium leptogaster'', but Leuckart did not see the animal. The species was then mentioned by Félix Dujardin and Karl Moriz Diesing, who also did not see the specimens. However, Diesing transferred the species to the genus '' Discocotyle'' but also considered the species as "species inquirenda". Later, in 1858, Diesing transferred the species to the genus ''Placoplectanum''. Olsson redescribed the animal in 1876 Olsson, P. (1876). Bidrag till ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motility, able to move, can Sexual reproduction, reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of Cell (biology), cells, the blastula, during Embryogenesis, embryonic development. Over 1.5 million Extant taxon, living animal species have been Species description, described—of which around 1 million are Insecta, insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have Ecology, complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a Symmetry in biology#Bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Moriz Diesing
Karl (Carl) Moriz (Moritz) Diesing (16 June 1800, in Krakow – 10 January 1867, in Vienna) was an Austrian naturalist and zoologist, specializing in the study of helminthology. He studied medicine at the University of Vienna, earning his doctorate in 1826. Afterwards, he served as an assistant to botanist Nikolaus Joseph von Jacquin, later working as an intern at the ''Hof-Naturalien-Cabinet'' (from 1829). In 1836 he became a curator of the zoological collections. In the late 1840s, he began to suffer from serious eye problems, and shortly afterwards experienced permanent blindness. His principal works include ''Systema Helminthum'' (2 vols., 1850–1851), and ''Revision der Nematoden'' (1861). In his paper "''Versuch einer monographie der Gattung Pentastoma''" (Ann. Wien Mus. Naturges. 1836, 1–32), he was the first to establish the distinct nature of the Pentastomida, placing them in a new group which he called Acanthotheca. The genera ''Diesingia'' and ''Diesingiella'' < ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of Norway
Fauna of Norway may refer to: * List of birds of Norway * List of mammals of Norway The following is a list of mammals with non-domesticated populations in Norway. Insectivores Hedgehogs *European hedgehog, ''Erinaceus europaeus'' Shrews *Eurasian water shrew, ''Neomys fodiens'' *Common shrew, ''Sorex araneus'' * Laxmann's s ... See also * Outline of Norway {{Short pages monitor ... [...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] |
Spermiogenesis
Spermiogenesis is the final stage of spermatogenesis, during which the spermatids develop into mature spermatozoa. At the beginning of the stage, the spermatid is a more or less circular cell containing a nucleus, Golgi apparatus, centriole and mitochondria; by the end of the process, it has radically transformed into an elongated spermatozoon, complete with a head, midpiece, and tail. Phases The process of spermiogenesis is traditionally divided into four stages: the Golgi phase, the cap phase, formation of the tail, and the maturation stage. Golgi phase The spermatids, which up until now have been mostly radially symmetrical, begin to develop polarity. The head forms at one end, where the Golgi apparatus creates enzymes that will become the acrosome. At the other end, it develops a thickened midpiece, where the mitochondria gather and the distal centriole begins to form an axoneme. Spermatid DNA also undergoes packaging, becoming highly condensed. The DNA is first packa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vagina
In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen. At the deep end, the cervix (neck of the uterus) bulges into the vagina. The vagina allows for sexual intercourse and birth. It also channels menstrual flow, which occurs in humans and closely related primates as part of the menstrual cycle. Although research on the vagina is especially lacking for different animals, its location, structure and size are documented as varying among species. Female mammals usually have two external openings in the vulva; these are the urethral opening for the urinary tract and the vaginal opening for the genital tract. This is different from male mammals, who usually have a single urethral opening for both urination and reproduction. The vaginal opening is much larger than the nearby urethral opening, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmission Electron Microscopy
Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a grid. An image is formed from the interaction of the electrons with the sample as the beam is transmitted through the specimen. The image is then magnified and focused onto an imaging device, such as a fluorescent screen, a layer of photographic film, or a sensor such as a scintillator attached to a charge-coupled device. Transmission electron microscopes are capable of imaging at a significantly higher resolution than light microscopes, owing to the smaller de Broglie wavelength of electrons. This enables the instrument to capture fine detail—even as small as a single column of atoms, which is thousands of times smaller than a resolvable object seen in a light microscope. Transmission electron microscopy is a major analytical method i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clamp (zoology)
Clamps are the main attachment structure of the Polyopisthocotylean monogeneans. Bychowsky, B. E. (1957) Monogenetic Trematodes. Their systematic and phylogeny. Akad. Nauka. USSR. English translation by the American Institute of Biological Science, Washington. 509 pp. These ectoparasitic worms have a variable number of clamps on their haptor (the posterior attachment organ); each clamp is attached to the host fish, generally to its gill. Clamps include sclerotised elements, called the sclerites, and muscles Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle .... The structure of clamps varies according to the groups within the Polyopisthocotylean monogeneans; microcotylids have relatively simple clamps, whereas gastrocotylids have more complex clamps. References {{Reflist Platyhel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haptor
The haptor is the attachment organ of the monogeneans, a group of parasitic Platyhelminthes. The haptor is sometimes called opisthaptor (from ''opistho-'': behind) to emphasize that it is located in the posterior part of the body, and to differentiate it from the prohaptor (from ''pro-'': in front), a structure including glands located at the anterior part of the body. According to Yamaguti (1963), the chief adhesive organ of the monogeneans, the haptor, is posterior, more or less discoid, muscular, may be divided into alveoli or loculi, is usually provided with anchors, has nearly always marginal larval hooklets, or is in a reduced form with anchors. The haptor may consist of symmetrical or asymmetrical, sessile or pedunculate, muscular suckers or clamps with or without supporting sclerites; accessory adhesive organs may be present in form of armed plaques, lappets or appendices. The structure of the haptor is different in the two major groups constituting the Monogenea, nam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, Finland to the east, and is connected to Denmark in the southwest by a bridgetunnel across the Öresund. At , Sweden is the largest Nordic country, the third-largest country in the European Union, and the fifth-largest country in Europe. The capital and largest city is Stockholm. Sweden has a total population of 10.5 million, and a low population density of , with around 87% of Swedes residing in urban areas in the central and southern half of the country. Sweden has a nature dominated by forests and a large amount of lakes, including some of the largest in Europe. Many long rivers run from the Scandes range through the landscape, primarily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norway
Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of Norway. Bouvet Island, located in the Subantarctic, is a dependency of Norway; it also lays claims to the Antarctic territories of Peter I Island and Queen Maud Land. The capital and largest city in Norway is Oslo. Norway has a total area of and had a population of 5,425,270 in January 2022. The country shares a long eastern border with Sweden at a length of . It is bordered by Finland and Russia to the northeast and the Skagerrak strait to the south, on the other side of which are Denmark and the United Kingdom. Norway has an extensive coastline, facing the North Atlantic Ocean and the Barents Sea. The maritime influence dominates Norway's climate, with mild lowland temperatures on the se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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