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Johannes Schmidt (biologist)
Ernst Johannes Schmidt (2 January 1877 – 21 February 1933) was a Danish biologist credited with discovering in 1920 that European eels migrate to the Sargasso Sea to spawn. Before this people in North America and Europe had wondered where the small glass eels, or elvers, came from. Biography Schmidt was born at Jægerspris, Denmark, son of Ernst Schmidt and Camilla Ellen Sophie Schmidt (born Kjeldall and sister to the chemist Johan Kjeldahl). Schmidt began his studies of natural history at the University of Copenhagen under professor of botany Eugen Warming (1841–1924), and obtained an MS degree in biology in 1898. He obtained a grant from the Carlsberg Foundation to study the flora of the coastal areas of Ko Chang in then Siam, including both mangrove trees and microalgae. He made his doctoral thesis in biology and botany, on shoot architecture of mangrove trees and Eugen Warming served as faculty opponent in October 1903. Schmidt then more or less switched to marine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CREDENTIAL
A credential is a piece of any document that details a qualification, competence, or authority issued to an individual by a third party with a relevant or ''de facto'' authority or assumed competence to do so. Examples of credentials include academic diplomas, academic degrees, Professional certification, certifications, security clearances, Identity document, identification documents, badges, passwords, user names, key (lock), keys, power of attorney, powers of attorney, and so on. Sometimes publications, such as scientific papers or books, may be viewed as similar to credentials by some people, especially if the publication was peer reviewed or made in a well-known Academic journal, journal or reputable publisher. Types and documentation of credentials A person holding a credential is usually given documentation or secret knowledge (''e.g.,'' a password or key) as proof of the credential. Sometimes this proof (or a copy of it) is held by a third, trusted party. While in some c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ko Chang
Ko Chang (, ) is an amphoe (district) in Trat province, Thailand. It is on the Gulf of Thailand's eastern seaboard, from Bangkok, near the border with Cambodia., archive-url=//web.archive.org/web/20200113104227/https://www.tourismthailand.org/Destinations/Provinces/ko-chang/467, archive-date=13 January 2020, url-status=live The island Ko Chang occupies most of the district's land area, along with several smaller islands. With an area of , Ko Chang is the third-largest island in Thailand by area, after Phuket and Ko Samui. The name Ko Chang means 'Elephant Island' and derives from its elephant-shaped headland. Despite the presence of elephants on the island, they are not indigenous. At present, there are eight villages on the island. History Prior to World War II, Ko Chang was little known. During this period, the few families there made a living growing coconuts and fruits. On 17 January 1941, Ko Chang was the scene of the Battle of Ko Chang between the Royal Thai Navy and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humulus
''Humulus'', or hop, is a small genus of flowering plants in the family Cannabaceae. The hop is native to temperate regions of the Northern Hemisphere. Hops are the female flowers (seed cones, strobiles) of the hop species '' H. lupulus''; as a main flavor and aroma ingredient in many beer styles, ''H. lupulus'' is widely cultivated for use by the brewing industry. Description Although frequently referred to in American literature as the hops "vine", it is technically a bine; unlike vines, which use tendrils, suckers, and other appendages for attaching themselves, bines have stout stems with stiff hairs to aid in climbing. In British literature the term "vine" is generally reserved for the grape genus ''Vitis''. ''Humulus'' is described as a twining perennial herbaceous plant which sends up new shoots in early spring and dies back to the cold-hardy rhizome in autumn. Hop shoots grow very rapidly, and at the peak of growth can grow per week. Hop bines climb by wrapping clockwise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Phenotypic trait, Trait inheritance and Molecular genetics, molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the Cell (bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Physiology
Plant physiology is a subdiscipline of botany concerned with the functioning, or physiology, of plants. Plant physiologists study fundamental processes of plants, such as photosynthesis, respiration, plant nutrition, plant hormone functions, tropisms, nastic movements, photoperiodism, photomorphogenesis, circadian rhythms, environmental stress physiology, seed germination, dormancy and stomata function and transpiration. Plant physiology interacts with the fields of plant morphology (structure of plants), plant ecology (interactions with the environment), phytochemistry (biochemistry of plants), cell biology, genetics, biophysics and molecular biology. Aims The field of plant physiology includes the study of all the internal activities of plants—those chemical and physical processes associated with life as they occur in plants. This includes study at many levels of scale of size and time. At the smallest scale are molecular interactions of photosynthesis and internal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diatom
A diatom (Neo-Latin ''diatoma'') is any member of a large group comprising several Genus, genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of Earth's Biomass (ecology), biomass. They generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion tonnes of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans. The Protist shell, shells of dead diatoms are a significant component of marine sediment, and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by transatlantic winds from the African Sahara, much of it from the Bodélé Depression, which was once made up of a system of fresh-water lakes. Diatoms are unicellular organisms: they occur either as solitary cells or in Colony (biology), colonies, which can take the shape of ribb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanobacteria
Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis. The name "cyanobacteria" () refers to their bluish green (cyan) color, which forms the basis of cyanobacteria's informal common name, blue-green algae. Cyanobacteria are probably the most numerous taxon to have ever existed on Earth and the first organisms known to have produced oxygen, having appeared in the middle Archean eon and apparently originated in a freshwater or terrestrial environment. Their photopigments can absorb the red- and blue-spectrum frequencies of sunlight (thus reflecting a greenish color) to split water molecules into hydrogen ions and oxygen. The hydrogen ions are used to react with carbon dioxide to produce complex organic compounds such as carbohydrates (a process known as carbon fixation), and the oxygen is released as a byproduct. By continuously producing and releasing oxygen over billions of years, cyanobacte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocyst
Heterocysts or heterocytes are specialized nitrogen-fixing cells formed during nitrogen starvation by some filamentous cyanobacteria, such as ''Nostoc'', ''Cylindrospermum'', and '' Anabaena''. They fix nitrogen from dinitrogen (N2) in the air using the enzyme nitrogenase, in order to provide the cells in the filament with nitrogen for biosynthesis. Nitrogenase is inactivated by oxygen, so the heterocyst must create a microanaerobic environment. The heterocysts' unique structure and physiology require a global change in gene expression. For example, heterocysts: * produce three additional cell walls, including one of glycolipid that forms a hydrophobic barrier to oxygen * produce nitrogenase and other proteins involved in nitrogen fixation * degrade photosystem II, which produces oxygen * up-regulate glycolytic enzymes * produce proteins that scavenge any remaining oxygen * contain polar plugs composed of cyanophycin which slows down cell-to-cell diffusion Cyanobacteria usu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richelia
''Richelia'' is a genus of Nitrogen fixation, nitrogen-fixing, Filamentous bacteria, filamentous, heterocystous and cyanobacteria. It contains the single species ''Richelia intracellularis''. They exist as both free-living organisms as well as Symbiotic bacteria, symbionts within potentially up to 13 diatoms distributed throughout the global ocean. As a Symbiotic bacteria, symbiont, ''Richelia'' can associate Epiphysis, epiphytically and as endosymbionts within the periplasmic space between the cell membrane and cell wall of diatoms. Morphology ''Richelia'' are made up of filaments called trichomes, which are fine hair-like structures that grow out of a myriad of plant species, though their presence as free-living organisms in the Marine habitats, marine environment is rare. The number of trichomes ''Richelia'' have in each diatom Host (biology), host varies. The trichomes serve the purpose of nitrogen fixation as well as nutrient exchange with Host (biology), host diatoms. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phycology
Phycology () is the scientific study of algae. Also known as algology, phycology is a branch of life science. Algae are important as primary producers in aquatic ecosystems. Most algae are eukaryotic, photosynthetic organisms that live in a wet environment. They are distinguished from the higher plants by a lack of true roots, stems or leaves. They do not produce flowers. Many species are single-celled and microscopic (including phytoplankton and other microalgae); many others are multicellular to one degree or another, some of these growing to large size (for example, seaweeds such as kelp and '' Sargassum''). A number of microscopic algae also occur as symbionts in lichens. Phycologists typically focus on either freshwater or ocean algae, and further within those areas, either diatoms or soft algae. History of phycology While both the ancient Greeks and Romans knew of algae, and the ancient Chinese even cultivated certain varieties as food, the scientific study of alg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carlsberg Laboratory
The Carlsberg Research Laboratory is a private scientific research center in Copenhagen, Denmark under the Carlsberg Foundation. It was founded in 1875 by J. C. Jacobsen, the founder of the Carlsberg brewery, with the purpose of advancing biochemical knowledge, especially relating to brewing. It featured a Department of Chemistry and a Department of Physiology. In 1972, the laboratory was renamed the Carlsberg Research Center and was transferred to the brewery. Overview The Carlsberg Laboratory was known for isolating ''Saccharomyces carlsbergensis'', the species of yeast responsible for lager beer, lager Fermentation (food), fermentation, as well as introducing the concept of pH in acid-base chemistry. The Danes, Danish chemist Soren Peder Lauritz Sorensen, Søren Peder Lauritz Sørensen introduced the concept of pH, a scale for measuring acidity and basicity of Chemical substance, substances. While working at the Carlsberg Laboratory, he studied the effect of ion concentration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoology
Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and how they interact with their ecosystems. Zoology is one of the primary branches of biology. The term is derived from Ancient Greek , ('animal'), and , ('knowledge', 'study'). Although humans have always been interested in the natural history of the animals they saw around them, and used this knowledge to domesticate certain species, the formal study of zoology can be said to have originated with Aristotle. He viewed animals as living organisms, studied their structure and development, and considered their adaptations to their surroundings and the function of their parts. Modern zoology has its origins during the Renaissance and early modern period, with Carl Linnaeus, Antonie van Leeuwenhoek, Robert Hooke, Charles Darwin, Gregor Mendel a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
