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Crossbridge
The sliding filament theory explains the mechanism of muscle contraction based on muscle proteins that slide past each other to generate movement. According to the sliding filament theory, the myosin ( thick filaments) of muscle fibers slide past the actin ( thin filaments) during muscle contraction, while the two groups of filaments remain at relatively constant length. The theory was independently introduced in 1954 by two research teams, one consisting of Andrew Huxley and Rolf Niedergerke from the University of Cambridge, and the other consisting of Hugh Huxley and Jean Hanson from the Massachusetts Institute of Technology. It was originally conceived by Hugh Huxley in 1953. Andrew Huxley and Niedergerke introduced it as a "very attractive" hypothesis. Before the 1950s there were several competing theories on muscle contraction, including electrical attraction, protein folding, and protein modification. The novel theory directly introduced a new concept called cross-bridge t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscle Contraction
Muscle contraction is the activation of tension-generating sites within muscle cells. In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as when holding something heavy in the same position. The termination of muscle contraction is followed by muscle relaxation, which is a return of the muscle fibers to their low tension-generating state. For the contractions to happen, the muscle cells must rely on the interaction of two types of filaments which are the thin and thick filaments. Thin filaments are two strands of actin coiled around each, and thick filaments consist of mostly elongated proteins called myosin. Together, these two filaments form myofibrils which are important organelles in the skeletal muscle system. Muscle contraction can also be described based on two variables: length and tension. A muscle contraction is described as isometric if the muscle tension change ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-bridge Cycle
Muscle contraction is the activation of tension-generating sites within muscle cells. In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in muscle length, such as when holding something heavy in the same position. The termination of muscle contraction is followed by muscle relaxation, which is a return of the muscle fibers to their low tension-generating state. For the contractions to happen, the muscle cells must rely on the interaction of two types of filaments which are the thin and thick filaments. Thin filaments are two strands of actin coiled around each, and thick filaments consist of mostly elongated proteins called myosin. Together, these two filaments form myofibrils which are important organelles in the skeletal muscle system. Muscle contraction can also be described based on two variables: length and tension. A muscle contraction is described as isometric if the muscle tension changes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sliding Filament Theory
The sliding filament theory explains the mechanism of muscle contraction based on muscle proteins that slide past each other to generate movement. According to the sliding filament theory, the myosin ( thick filaments) of muscle fibers slide past the actin ( thin filaments) during muscle contraction, while the two groups of filaments remain at relatively constant length. The theory was independently introduced in 1954 by two research teams, one consisting of Andrew Huxley and Rolf Niedergerke from the University of Cambridge, and the other consisting of Hugh Huxley and Jean Hanson from the Massachusetts Institute of Technology. It was originally conceived by Hugh Huxley in 1953. Andrew Huxley and Niedergerke introduced it as a "very attractive" hypothesis. Before the 1950s there were several competing theories on muscle contraction, including electrical attraction, protein folding, and protein modification. The novel theory directly introduced a new concept called cross-bridge t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skeletal Muscle
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 tissue, and are often known as muscle fibers. The muscle tissue of a skeletal muscle is striated – having a striped appearance due to the arrangement of the sarcomeres. Skeletal muscles are voluntary muscles under the control of the somatic nervous system. The other types of muscle are cardiac muscle which is also striated and smooth muscle which is non-striated; both of these types of muscle tissue are classified as involuntary, or, under the control of the autonomic nervous system. A skeletal muscle contains multiple fascicles – bundles of muscle fibers. Each individual fiber, and each muscle is surrounded by a type of connective tissue layer of fascia. Muscle fibers are formed from the fusion of developmental myobla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brunó Ferenc Straub
Brunó Ferenc Straub (5 January 1914 in Nagyvárad, Austria-Hungary (now Oradea, Romania) – 15 February 1996) was a biochemist. As a young scholar he was a research assistant of Albert Szent-Györgyi at the University of Szeged, and subsequently worked at the Molteno Institute, Cambridge, UK. He is credited with the discovery of actin. He founded the Biological Research Centre in Szeged. He was the chairman of the Hungarian Presidential Council from 29 June 1988 to 23 October 1989. He proposed the theory of conformational selection in 1964; the same year the MWC model In biochemistry, the Monod-Wyman-Changeux model (MWC model, also known as the symmetry model) describes allosteric transitions of proteins made up of identical subunits. It was proposed by Jean-Pierre Changeux in his PhD thesis, and described by ... was proposed. External links {{DEFAULTSORT:Straub, Bruno Ferenc 1914 births 1996 deaths People from Oradea Members of the National Assembly of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Prize In Physiology Or Medicine
The Nobel Prize in Physiology or Medicine is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, according to Alfred Nobel's 1895 will, are awarded "to those who, during the preceding year, have conferred the greatest benefit to humankind". Nobel Prizes are awarded in the fields of Physics, Chemistry, Physiology or Medicine, Literature, and Peace. The Nobel Prize is presented annually on the anniversary of Alfred Nobel's death, 10 December. As of 2022, 114 Nobel Prizes in Physiology or Medicine have been awarded to 226 laureates, 214 men and 12 women. The first one was awarded in 1901 to the German physiologist, Emil von Behring, for his work on serum therapy and the development of a vaccine against diphtheria. The first woman to receive the Nobel Prize in Physiology or Medicine, Gerty Cori, received it in 1947 for her role in elucidat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin C
Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) and wrinkles on the face. It is used to prevent and treat scurvy. Vitamin C is an essential nutrient involved in the repair of tissue, the formation of collagen, and the enzymatic production of certain neurotransmitters. It is required for the functioning of several enzymes and is important for immune system function. It also functions as an antioxidant. Most animals are able to synthesize their own vitamin C. However, apes (including humans) and monkeys (but not all primates), most bats, some rodents, and certain other animals must acquire it from dietary sources. There is some evidence that regular use of supplements may reduce the duration of the common cold, but it does not appear to prevent infection. It is unclear whether ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fumaric Acid
Fumaric acid is an organic compound with the formula HO2CCH=CHCO2H. A white solid, fumaric acid occurs widely in nature. It has a fruit-like taste and has been used as a food additive. Its E number is E297. The salts and esters are known as fumarates. Fumarate can also refer to the ion (in solution). Fumaric acid is the trans isomer of butenedioic acid, while maleic acid is the cis isomer. Biosynthesis and occurrence It is produced in eukaryotic organisms from succinate in complex 2 of the electron transport chain via the enzyme succinate dehydrogenase. It is one of two isomeric unsaturated dicarboxylic acids, the other being maleic acid. In fumaric acid the carboxylic acid groups are ''trans'' (''E'') and in maleic acid they are ''cis'' (''Z''). Fumaric acid is found in fumitory (''Fumaria officinalis''), bolete mushrooms (specifically ''Boletus fomentarius var. pseudo-igniarius''), lichen, and Iceland moss. Fumarate is an intermediate in the citric acid cycle us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarcomere
A sarcomere (Greek σάρξ ''sarx'' "flesh", μέρος ''meros'' "part") is the smallest functional unit of striated muscle tissue. It is the repeating unit between two Z-lines. Skeletal muscles are composed of tubular muscle cells (called muscle fibers or myofibers) which are formed during embryonic myogenesis. Muscle fibers contain numerous tubular myofibrils. Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as alternating dark and light bands. Sarcomeres are composed of long, fibrous proteins as filaments that slide past each other when a muscle contracts or relaxes. The costamere is a different component that connects the sarcomere to the sarcolemma. Two of the important proteins are myosin, which forms the thick filament, and actin, which forms the thin filament. Myosin has a long, fibrous tail and a globular head, which binds to actin. The myosin head also binds to ATP, which is the source of energy for muscle movement. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Fritz Meyerhof
Otto Fritz Meyerhof (; April 12, 1884 – October 6, 1951) was a German physician and biochemist who won the 1922 Nobel Prize in Physiology and Medicine. Biography Otto Fritz Meyerhof was born in Hannover, at Theaterplatz 16A (now:Rathenaustrasse 16A), the son of wealthy Jewish parents. In 1888, his family moved to Berlin, where Otto spent most of his childhood, and where he started his study of medicine. He continued these studies in Strasbourg and Heidelberg, from which he graduated in 1909, with a work titled "Contributions to the Psychological Theory of Mental Illness". In Heidelberg, he met Hedwig Schallenberg. They married in 1914 and became parents of a daughter, Bettina, and two sons, Gottfried (who referred, after emigration, to himself as Geoffrey) as well as Walter. In 1912, Otto Meyerhof moved to the University of Kiel, where he received a professorship in 1918. In 1922, he was awarded the Nobel Prize in Medicine, with Archibald Vivian Hill, for his work on mus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albert Szent-Györgyi
Albert Imre Szent-Györgyi de Nagyrápolt ( hu, nagyrápolti Szent-Györgyi Albert Imre; September 16, 1893 – October 22, 1986) was a Hungarian biochemist who won the Nobel Prize in Physiology or Medicine in 1937. He is credited with first isolating vitamin C and discovering the components and reactions of the citric acid cycle. He was also active in the Hungarian Resistance during World War II, and entered Hungarian politics after the war. Early life Szent-Györgyi was born in Budapest, Kingdom of Hungary in 1893. His father, Miklós Szent-Györgyi, was a landowner, born in Marosvásárhely, Transylvania (today Târgu Mureş, Romania), a Calvinist, and could trace his ancestry back to 1608 when Sámuel, a Calvinist predicant, was ennobled. At the time of Szent-Györgyi's birth, being of the nobility was considered important and created opportunities that otherwise were not available. (Miklós Szent-Györgyi's parents were Imre Szent-Györgyi and Mária Csiky). Hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francis O
Francis may refer to: People * Pope Francis, the head of the Catholic Church and sovereign of the Vatican City State and Bishop of Rome * Francis (given name), including a list of people and fictional characters *Francis (surname) Places *Rural Municipality of Francis No. 127, Saskatchewan, Canada *Francis, Saskatchewan, Canada **Francis (electoral district) * Francis, Nebraska *Francis Township, Holt County, Nebraska *Francis, Oklahoma * Francis, Utah Other uses * ''Francis'' (film), the first of a series of comedies featuring Francis the Talking Mule, voiced by Chill Wills *''Francis'', a 1983 play by Julian Mitchell * FRANCIS, a bibliographic database * ''Francis'' (1793), a colonial schooner in Australia * Francis turbine, a type of water turbine * Francis (band), a Sweden-based folk band * Francis, a character played by YouTuber Boogie2988 See also * Saint Francis (other) * Francies, a surname, including a list of people with the name * Francisco (other) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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