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Pitvipers
The Crotalinae, commonly known as pit vipers,Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . crotaline snakes (from grc, κρόταλον ''krotalon'' castanet), or pit adders, are a subfamily (biology), subfamily of Viperidae, vipers found in Eurasia and the Americas. Like all other vipers, they are venomous snake, venomous. They are distinguished by the presence of a Infrared sensing in snakes, heat-sensing pit organ located between the eye and the nostril on both sides of the head. Currently, 23 genus, genera and 155 species are recognized: These are also the only Viperidae, viperids found in the Americas. The groups of snakes represented here include rattlesnakes, Bothrops, lanceheads, and Trimeresurus, Asian pit vipers. The type genus for this subfamily is ''Crotalus'', of which the type species is the timber rattlesnake, ''C. horridus''. These snakes range in size from the diminutive hump-nosed viper, ''Hypnale hypnal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Sensing In Snakes
The ability to sense infrared thermal radiation evolved independently in two different groups of snakes, one consisting of the families Boidae (boas) and Pythonidae (pythons), the other of the family Crotalinae (pit vipers). What is commonly called a pit organ allows these animals to essentially "see" radiant heat at wavelengths between 5 and 30 Micrometre, μm. The more advanced infrared sense of pit vipers allows these animals to strike prey accurately even in the absence of light, and detect warm objects from several meters away. It was previously thought that the organs evolved primarily as prey detectors, but recent evidence suggests that it may also be used in thermoregulation and predator detection, making it a more general-purpose sensory organ than was supposed.Greene HW. 1992. The ecological and behavioral context for pitviper evolution. ''In'' Campbell JA, Brodie ED Jr. 1992. Biology of the Pitvipers. Texas: Selva. 467 pp. 17 plates. . Phylogeny and evolution The fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Sensing In Snakes
The ability to sense infrared thermal radiation evolved independently in two different groups of snakes, one consisting of the families Boidae (boas) and Pythonidae (pythons), the other of the family Crotalinae (pit vipers). What is commonly called a pit organ allows these animals to essentially "see" radiant heat at wavelengths between 5 and 30 Micrometre, μm. The more advanced infrared sense of pit vipers allows these animals to strike prey accurately even in the absence of light, and detect warm objects from several meters away. It was previously thought that the organs evolved primarily as prey detectors, but recent evidence suggests that it may also be used in thermoregulation and predator detection, making it a more general-purpose sensory organ than was supposed.Greene HW. 1992. The ecological and behavioral context for pitviper evolution. ''In'' Campbell JA, Brodie ED Jr. 1992. Biology of the Pitvipers. Texas: Selva. 467 pp. 17 plates. . Phylogeny and evolution The fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimeresurus
''Trimeresurus'' is a genus of venomous pit vipers found in Asia from the Indian Subcontinent throughout Southeast Asia, China, and the Pacific Islands. Currently 44 species are recognized. Common names include Asian palm pit vipers,Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . Asian lanceheads, and green pit vipers.United States Navy (1991). ''Poisonous Snakes of the World''. New York: U.S. Government / Dover Publications Inc. 203 pp. . Description Most species in the genus ''Trimeresurus'' are relatively small, primarily arboreal species, with thin bodies and prehensile tails. Most ''Trimeresurus'' species are typically green in color, but some species also have yellow, black, orange, red, or gold markings. Feeding The diet of ''Trimeresurus'' species includes a variety of animals, including lizards, amphibians, birds, rodents, and other small mammals. Reproduction Like most viper species, many of the species in the genus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicolaus Michael Oppel
Nicolaus Michael Oppel (December 7, 1782 in Schönficht – February 16, 1820 in Munich) was a German naturalist. He was a student of, and worked as an assistant to, André Marie Constant Duméril (1774-1860) at the Muséum national d'histoire naturelle in Paris, France, cataloging and classifying species of reptiles. In 1811 he published a book entitled ''Die Ordnungen, Familien und Gattungen der Reptilien als Prodrom einer Naturgeschichte derselben'', or "The Orders, Families, and Types of Reptiles..." in which he established the order, Squamata, and the families Cheloniidae, Colubridae, and the subfamily Crotalinae, as well as several genera which are still in use by taxonomists today. With Friedrich Tiedemann (1781-1861) and Joseph Liboschitz (1783-1824), he was co-author of ''Naturgeschichte der Amphibien'' ( Natural history of amphibians Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypnale Hypnale
''Hypnale hypnale'' is a venomous pit viper species endemic to India and Sri Lanka. Common names include the hump-nosed viper,United States Navy (1991). ''Poisonous Snakes of the World''. New York: United States Government/Dover Publications Inc. 203 pp. . Merrem's hump-nosed viperDefense Pest Management Information Analysis Center (2001). ''Regional Disease Vector Ecology Profile for South Central Asia''. 219 ppPDF aArmed Forces Pest Management Board Accessed 17 November 2006. and others listed below at § Common names.'' No subspecies are currently recognized. Description ''H. hypnale'' grows to an average of 30–45 cm (11¾-17¾ inches) in total length (including tail). The Armed Forces Pest Management Board states 0.4-0.6 m (15¾-23⅝ inches) in total length. Its build is that of a typical viperid with a stout body and a wide head. The snout is pointed and turned upwards, ending in a hump. The frontal, supraoculars, and parietal shields are large, but those on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rangefinder
A rangefinder (also rangefinding telemeter, depending on the context) is a device used to measure distances to remote objects. Originally optical devices used in surveying, they soon found applications in other fields, such as photography and in the military. They were specially useful for finding the range of a target, such as in naval gunnery and anti-aircraft artillery. The word ''telemeter'' is derived . Designs The first rangefinder telemeter was invented by James Watt in 1769 and put to use in 1771 in surveying canals. Watt called his instrument a micrometer, a term now used with a different meaning in engineering (the micrometer screw gauge). It consisted of two parallel hairs in the focal plane of a telescope eyepiece crossing an upright hair. At the point to be measured, two sliding targets on a surveyor's rod were adjusted to align with the hairs in the telescope. The distance to the rod could then be determined from the distance between the targets on the ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylcholine Esterase
Acetylcholinesterase (HGNC symbol ACHE; EC 3.1.1.7; systematic name acetylcholine acetylhydrolase), also known as AChE, AChase or acetylhydrolase, is the primary cholinesterase in the body. It is an enzyme that catalyzes the breakdown of acetylcholine and some other choline esters that function as neurotransmitters: : acetylcholine + H2O = choline + acetate It is found at mainly neuromuscular junctions and in chemical synapses of the cholinergic type, where its activity serves to terminate synaptic transmission. It belongs to the carboxylesterase family of enzymes. It is the primary target of inhibition by organophosphorus compounds such as nerve agents and pesticides. Enzyme structure and mechanism AChE is a hydrolase that hydrolyzes choline esters. It has a very high catalytic activity—each molecule of AChE degrades about 25,000 molecules of acetylcholine (ACh) per second, approaching the limit allowed by diffusion of the substrate. The active site of AChE comprises ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esterase
An esterase is a hydrolase enzyme that splits esters into an acid and an alcohol in a chemical reaction with water called hydrolysis. A wide range of different esterases exist that differ in their substrate specificity, their protein structure, and their biological function. EC classification/list of enzymes * ''EC 3.1.1'': Carboxylic ester hydrolases ** Acetylesterase (EC 3.1.1.6), splits off acetyl groups *** Cholinesterase **** Acetylcholinesterase, inactivates the neurotransmitter acetylcholine **** Pseudocholinesterase, broad substrate specificity, found in the blood plasma and in the liver ** Pectinesterase (EC 3.1.1.11), clarifies fruit juices * ''EC 3.1.2'': Thiolester hydrolases ** Thioesterase *** Ubiquitin carboxy-terminal hydrolase L1 * ''EC 3.1.3'': Phosphoric monoester hydrolases ** Phosphatase (EC 3.1.3.x), hydrolyses phosphoric acid monoesters into a phosphate ion and an alcohol *** Alkaline phosphatase, removes phosphate groups from many types of molecules, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoamine Oxidase
Monoamine oxidases (MAO) () are a family of enzymes that catalyze the oxidation of monoamines, employing oxygen to clip off their amine group. They are found bound to the outer membrane of mitochondria in most cell types of the body. The first such enzyme was discovered in 1928 by Mary Bernheim in the liver and was named tyramine oxidase. The MAOs belong to the protein family of flavin-containing amine oxidoreductases. MAOs are important in the breakdown of monoamines ingested in food, and also serve to inactivate monoamine neurotransmitters. Because of the latter, they are involved in a number of psychiatric and neurological diseases, some of which can be treated with monoamine oxidase inhibitors (MAOIs) which block the action of MAOs. Subtypes and tissue distribution In humans there are two types of MAO: MAO-A and MAO-B. * Both are found in neurons and astroglia. * Outside the central nervous system: ** MAO-A is also found in the liver, pulmonary vascular endothelium, gas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine Triphosphate
Adenosine triphosphate (ATP) is an organic compound that provides energy to drive many processes in living cells, such as muscle contraction, nerve impulse propagation, condensate dissolution, and chemical synthesis. Found in all known forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer. When consumed in metabolic processes, it converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. The human body recycles its own body weight equivalent in ATP each day. It is also a precursor to DNA and RNA, and is used as a coenzyme. From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the Polyphosphate, triphosphate. Structure ATP consists of an adenine attached by the 9-nitrogen atom to the 1′ carbon atom of a sugar (ribose), which i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondria
A mitochondrion (; ) is an organelle found in the Cell (biology), cells of most Eukaryotes, such as animals, plants and Fungus, fungi. Mitochondria have a double lipid bilayer, membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'' was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase coined by Philip Siekevitz in a 1957 article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids and diplomonads, have reduced or transformed their mitochondria into mitosome, other structures. One eukaryote, ''Monocercomonoides'', is known to have completely lost its mitocho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pythonidae
The Pythonidae, commonly known as pythons, are a family of nonvenomous snakes found in Africa, Asia, and Australia. Among its members are some of the largest snakes in the world. Ten genera and 42 species are currently recognized. Distribution and habitat Pythons are found in sub-Saharan Africa, Nepal, India, Bangladesh, Sri Lanka, Southeast Asia, southeastern Pakistan, southern China, the Philippines and Australia. In the United States, an introduced population of Burmese pythons, ''Python bivittatus'', has existed as an invasive species in the Everglades National Park since the late 1990s. Common names * Sinhala - පිඹුරා (''Pimbura'') *Telugu - కొండచిలువ (Kondachiluva) * Odia - ଅଜଗର (Ajagara) *Malayalam - പെരുമ്പാമ്പ് (perumpāmp) *Hindi - अजगर ('Ajgar') Conservation Many species have been hunted aggressively, which has greatly reduced the population of some, such as the Indian python, ''Python molu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
