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Rhynchosciara Americana
''Rhynchosciara americana'' is a species of fly. It has a life cycle of approximately 70 days, and the sibling larvae show a synchronized development. The larvae can reach one inch in length, and the adult fly is about 0.8 inch (20 mm). The larvae groups are usually originated from the same female posture and spin a communal cocoon where the metamorphosis will occur. The fly is scientifically notable for the physiology of its polytene chromosomes and developmentally regulated amplified puffs, first observed by Crodowaldo Pavan. Its ecology is poorly understood, but it is assumed to be a fungus gnat. Until recently, scientists had no success in the laboratory breeding of this fly. Entomologist Christian Rudolph Wilhelm Wiedemann first described and classified this species in his work ''Diptera Exotica'' (1821). He had analyzed Brazilian specimens probably sent to him by colleagues or enthusiasts. European entomologists had difficulty visiting Brazil to collect samples ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christian Rudolph Wilhelm Wiedemann
Christian Rudolph Wilhelm Wiedemann (7 December 1770 – 31 December 1840) was a German physician, historian, naturalist and entomologist. He is best known for his studies of world Diptera, but he also studied Hymenoptera and Coleoptera, although far less expertly. Biography Wiedemann’s father, Conrad Eberhard Wiedemann (1722–1804) was an art dealer and his mother, Dorothea Frederike (née Raspe) (1741–1804) was the daughter of an accountant in the Royal Mining Service and also interested in the arts. After his education in Brunswick, he matriculated in 1790 to the Faculty of Medicine at the University of Jena where he was a contemporary of the poet Friedrich von Hardenberg. While attending university, Wiedemann, was one of the many pupils of Johann Friedrich Blumenbach, and travelled to Saxony and Bohemia. He obtained his doctoral degree in 1792 with a thesis entitled ''Dissertatio inauguralis sistens vitia gennus humanum debilitantia''. He then went to Englan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crodowaldo Pavan
Crodowaldo Pavan (; 1 December 1919 – 3 April 2009) was a Brazilian biologist and geneticist, and a scientific leader in Brazil. Early life Pavan was born to a family of second-generation immigrants from Italy in 1919, in the city of Campinas, São Paulo state, Brazil. His great-grandfather was an expert in textile paints and a militant anarchist, who was frequently persecuted and imprisoned in Italy as well as in Brazil for his political activism. As a boy, influenced by his father's porcelain manufacturing plant at Mogi das Cruzes, he wished to follow a career in engineering, but changed radically when he had the opportunity in high school to attend a lecture by noted French physician and professor André Dreyfus and a screening of the film " The Story of Louis Pasteur", starring Oscar-winning actor Paul Muni in the title role. Studies Following Dreyfus' advice, in 1938 he enrolled in a course of natural history at the University of São Paulo, continuing to work in biologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophilidae
The Drosophilidae are a diverse, cosmopolitan family of flies, which includes species called fruit flies, although they are more accurately referred to as vinegar or pomace flies. Another distantly related family of flies, Tephritidae, are true fruit flies because they are frugivorous, and include apple maggot flies and many pests. The best known species of the Drosophilidae is ''Drosophila melanogaster'', within the genus ''Drosophila'', also called the "fruit fly." ''Drosophila melanogaster'' is used extensively for studies concerning genetics, development, physiology, ecology and behaviour. Many fundamental biological mechanisms were discovered first in ''D. melanogaster.'' The fruit fly is mostly composed of post-mitotic cells, has a very short lifespan, and shows gradual aging. As in other species, temperature influences the life history of the animal. Several genes have been identified that can be manipulated to extend the lifespan of these insects. Additionally, '' Drosophi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
São Paulo (state)
São Paulo (, ) is one of the Federative units of Brazil, 26 states of the Brazil, Federative Republic of Brazil and is named after Paul the Apostle, Saint Paul of Tarsus. It is located in the Southeast Region, Brazil, Southeast Region and is bordered by the states of Minas Gerais to the north and northeast, Paraná (state), Paraná to the south, Rio de Janeiro (state), Rio de Janeiro to the east and Mato Grosso do Sul to the west, in addition to the Atlantic Ocean to the southeast. It is divided into List of municipalities in São Paulo, 645 municipalities. The total area is km2, which is equivalent to 2.9% of Brazil's surface, being slightly larger than the United Kingdom. Its capital is the São Paulo, municipality of São Paulo. With more than 44 million inhabitants in 2022, São Paulo is the Federative units of Brazil#List, most populous Brazilian state (around 22% of the Brazilian population), the List of first-level administrative divisions by population, world's 28th-mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chironomus
''Chironomus'' is a genus of nonbiting midges in the subfamily Chironominae of the bloodworm family, Chironomidae, containing several cryptic species that can only be distinguished by experts based on the characteristics of their giant chromosomes. In the early 20th century the name ''Tendipes'' Meigen, 1800 was often used instead. In 1963 the International Commission on Zoological Nomenclature restored the traditional name ''Chironomus''. Description Adult ''Chironomus'' are midges with the pronotum widest in the middle and bearing a notch, the head usually bearing a pair of small tubercles above the antennal bases, the antennal flagellum of males having 11 segments, and the male genitalia has inferior volsella large and larger than superior volsella. They range from 5 to 13 mm in length. Larvae are red and usually have tubes on the side or bottom of the eighth abdominal segment. These features are not unique to ''Chironomus'', also being found in some related genera. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymidine
Thymidine (nucleoside#List of nucleosides and corresponding nucleobases, symbol dT or dThd), also known as deoxythymidine, deoxyribosylthymine, or thymine deoxyriboside, is a pyrimidine nucleoside, deoxynucleoside. Deoxythymidine is the DNA nucleoside T, which pairs with deoxyadenosine (A) in double-stranded DNA. In cell biology it is used to cell synchronization, synchronize the cells in G1/early S phase. The prefix deoxy- is often left out since there are no precursors of thymine nucleotides involved in RNA synthesis. Before the boom in thymidine use caused by the need for thymidine in the production of the antiretroviral drug Zidovudine, azidothymidine (AZT), much of the world's thymidine production came from herring sperm. Thymidine occurs almost exclusively in DNA but it also occurs in the T arm, T-loop of tRNA. Structure and properties In its composition, deoxythymidine is a nucleoside composed of deoxyribose (a pentose sugar) joined to the pyrimidine base thymine. De ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription (genetics)
Transcription is the process of copying a segment of DNA into RNA for the purpose of gene expression. Some segments of DNA are transcribed into RNA molecules that can encode proteins, called messenger RNA (mRNA). Other segments of DNA are transcribed into RNA molecules called non-coding RNAs (ncRNAs). Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. In virology, the term transcription is used when referring to mRNA synthesis from a viral RNA molecule. The genome of many RNA viruses is composed of negative-sense RNA which acts as a template for positive sense viral messenger RNA - a necessary step in the synthesis of viral proteins needed for viral replication. This process is catalyzed by a viral RNA dependent RNA polymerase. Background A DNA transcription unit encoding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Replication
In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all life, living organisms, acting as the most essential part of heredity, biological inheritance. This is essential for cell division during growth and repair of damaged tissues, while it also ensures that each of the new cells receives its own copy of the DNA. The cell possesses the distinctive property of division, which makes replication of DNA essential. DNA is made up of a nucleic acid double helix, double helix of two Complementary DNA, complementary DNA strand, strands. DNA is often called double helix. The double helix describes the appearance of a double-stranded DNA which is composed of two linear strands that run opposite to each other and twist together. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila Melanogaster
''Drosophila melanogaster'' is a species of fly (an insect of the Order (biology), order Diptera) in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the "vinegar fly", "pomace fly", or "banana fly". In the wild, ''D. melanogaster'' are attracted to rotting fruit and fermenting beverages, and are often found in orchards, kitchens and pubs. Starting with Charles W. Woodworth's 1901 proposal of the use of this species as a model organism, ''D. melanogaster'' continues to be widely used for biological research in genetics, physiology, microbial pathogenesis, and Life history theory, life history evolution. ''D. melanogaster'' was the first animal to be Fruit flies in space, launched into space in 1947. As of 2017, six Nobel Prizes have been awarded to drosophilists for their work using the insect. ''Drosophila melanogaster'' is typically used in research owing to its rapid life cycle, relatively simple genetics with on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sciaridae
The Sciaridae are a family of fly, flies, commonly known as dark-winged fungus gnats. Commonly found in moist environments, they are known to be a pest of mushroom farms and are commonly found in household plant pots. This is one of the least studied of the large Diptera families, probably due to the small size of these insects and the similarity among species. Currently, around 1700 species are described, but an estimated 20,000 species are awaiting discovery, mainly in the tropics. More than 600 species are known from Europe. Description Adult Sciaridae are small, dark flies 1–11 mm long and usually <5 mm long. They have a characteristic wing venation: there is no cross vein except for a short rs at the wing base, the anterior veins are a short R1 and a long R5, vein M has a simple fork with a long stem, and CuA1 has a fork with a short stem. Larval Sciaridae are slender and lack legs. They are white except for a black head, and their skin is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
