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Micrurus Corallinus
''Micrurus corallinus'' is a species of highly venomous snake, venomous elapidae, elapid snake native to South America (Brazil, Argentina and Paraguay). There are no recognized subspecies. Common names Common names of this species include painted coral snake, ''cobra coral pintada'', ''mboi-chumbe'', ''vibora de coral'', ''boicora'', ''bocora'', ''coral-verdadeira'', ''ibiboboca'', and ''mboi-yvyvovo''. Description and Behavior The painted coral snake is a medium-sized tri-colored snake which can grow to , but most are closer to . It is a snake with nocturnal habits found on the coastlines, through leaves, on top of logs and stones, its diet is based on lizards, other snakes (including coluibrids), amphisbenids and gymnophils. The head color is black with a white or yellow back band, which narrows strongly in a dorsal shape, the bodies have wide red rings that are separated by a series of 15–27 (usually 17–21) by wide and narrow black rings and with white borders. The ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blasius Merrem
Blasius Merrem (4 February 1761 – 23 February 1824) was a German naturalist, zoologist, ornithologist, mathematician, and herpetologist. In 1804, he became the professor of political economy and botany at the University of Marburg. Early life Merrem was born at Bremen, and studied at the University of Göttingen under Johann Friedrich Blumenbach. He developed an interest in zoology, particularly ornithology. Ornithology He is remembered chiefly as the first ornithologist to propose a division of birds into Ratitae ( ratites or running birds, with a flat sternum) and Carinatae (carinates or flying birds, with a keeled sternum), which formed part of his classification of birds in ''Tentamen Systematis Naturalis Avium'', published in Berlin in 1816 (in ''Abhandlugen Akad. Wiss. Berlin 1812–1813: Phys. Kl.''). Herpetology Similarly, in his 1820 opus, ''Versuch eines Systems der Amphibien'', he was the first scientist to accurately separate amphibians from reptiles, to sep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LD50
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a toxin, radiation, or pathogen. The value of LD50 for a substance is the dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD50 is indicative of increased toxicity. The test was created by J.W. Trevan in 1927. The term semilethal dose is occasionally used in the same sense, in particular with translations of foreign language text, but can also refer to a sublethal dose. LD50 is usually determined by tests on animals such as laboratory mice. In 2011, the U.S. Food and Drug Administration approved alternative methods to LD50 for testing the cosmetic drug Botox without animal tests. Conventions The LD50 is usually expressed as the mass of substance administered per unit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptiles Of Paraguay
Reptiles, as most commonly defined are the animals in the Class (biology), class Reptilia ( ), a paraphyletic grouping comprising all sauropsid, sauropsids except birds. Living reptiles comprise turtles, crocodilians, Squamata, squamates (lizards and snakes) and rhynchocephalians (tuatara). As of March 2022, the Reptile Database includes about 11,700 species. In the traditional Linnaean taxonomy, Linnaean classification system, birds are considered a separate class to reptiles. However, crocodilians are more closely related to birds than they are to other living reptiles, and so modern Cladistics, cladistic classification systems include birds within Reptilia, redefining the term as a clade. Other cladistic definitions abandon the term reptile altogether in favor of the clade Sauropsida, which refers to all amniotes more closely related to modern reptiles than to mammals. The study of the traditional reptile Order (biology), orders, historically combined with that of modern amphi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptiles Of Argentina
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians (tuatara). As of March 2022, the Reptile Database includes about 11,700 species. In the traditional Linnaean classification system, birds are considered a separate class to reptiles. However, crocodilians are more closely related to birds than they are to other living reptiles, and so modern cladistic classification systems include birds within Reptilia, redefining the term as a clade. Other cladistic definitions abandon the term reptile altogether in favor of the clade Sauropsida, which refers to all amniotes more closely related to modern reptiles than to mammals. The study of the traditional reptile orders, historically combined with that of modern amphibians, is called herpetology. The earliest known proto-reptiles originated around 31 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptiles Of Brazil
Total number of species = 976 ''Nota bene'': In the following list, a binomial authority in parentheses indicates that the species was originally described in a genus other than the genus to which it is currently assigned. Testudines Cheloniidae (4 species) *''Caretta caretta'' (Linnaeus, 1758) *''Chelonia mydas'' (Linnaeus, 1758) *''Eretmochelys imbricata'' (Linnaeus, 1766) *''Lepidochelys olivacea'' (Eschscholtz, 1829) Dermochelyidae (1 species) *''Dermochelys coriacea'' (Linnaeus, 1766) Emydidae (2 species) *'' Trachemys adiutrix'' Vanzolini, 1995 *''Trachemys dorbigni'' ( A.M.C. Duméril & Bibron, 1835) Geoemydidae (1 species) *'' Rhinoclemmys punctularia'' (Daudin, 1801) Kinosternidae (1 species) *'' Kinosternon scorpioides'' (Linnaeus, 1766) Testudinidae (2 species) *''Geochelone carbonaria'' Spix, 1824 *''Geochelone denticulata'' (Linnaeus, 1766) Podocnemididae (5 species) *''Peltocephalus dumerilianus'' (Schweigger, 1812) *''Podocnemis erythrocephala'' (Spix, 1824 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snakes Of South America
Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints than their lizard ancestors, enabling them to swallow prey much larger than their heads (cranial kinesis). To accommodate their narrow bodies, snakes' paired organs (such as kidneys) appear one in front of the other instead of side by side, and most have only one functional lung. Some species retain a pelvic girdle with a pair of vestigial claws on either side of the cloaca. Lizards have evolved elongate bodies without limbs or with greatly reduced limbs about twenty-five times independently via convergent evolution, leading to many lineages of legless lizards. These resemble snakes, but several common groups of legless lizards have eyelids and external ears, which snakes lack, although this rule is not universal (see Amphisbaenia, Dibamida ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrurus
''Micrurus'' is a genus of venomous coral snakes of the family Elapidae. Geographic range Species in the genus ''Micrurus'' are endemic to the Americas. Species The following 83 species are recognized as being valid. *''Micrurus albicinctus'' Amaral, 1925 *''Micrurus alleni'' K. Schmidt, 1936 *''Micrurus altirostris'' (Cope, 1860) *''Micrurus ancoralis'' Jan, 1872 *''Micrurus annellatus'' W. Peters, 1871 *''Micrurus averyi'' K. Schmidt, 1939 *''Micrurus baliocoryphus'' (Cope, 1862) *''Micrurus bernadi'' (Cope, 1887) *''Micrurus bocourti'' (Jan, 1872) *''Micrurus bogerti'' Roze, 1967 *''Micrurus boicora'' *''Micrurus brasiliensis'' Roze, 1967 *''Micrurus browni'' K. Schmidt & H.M. Smith, 1943 *'' Micrurus carvalhoi'' Roze, 1967 *''Micrurus camilae'' Renjifo & Lundberg, 2003 *'' Micrurus circinalis'' ( A.M.C. Duméril, Bibron & A.H.A. Duméril, 1854) *''Micrurus clarki'' K. Schmidt, 1936 *''Micrurus collaris'' (Schlegel, 1837) *''Micrurus corallinus'' ( Merrem, 1820) *''Micr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholipase A2
The enzyme phospholipase A2 (EC 3.1.1.4, PLA2, systematic name phosphatidylcholine 2-acylhydrolase) catalyse the cleavage of fatty acids in position 2 of phospholipids, hydrolyzing the bond between the second fatty acid “tail” and the glycerol molecule: :phosphatidylcholine + H2O = 1-acylglycerophosphocholine + a carboxylate This particular phospholipase specifically recognizes the ''sn''2 acyl bond of phospholipids and catalytically hydrolyzes the bond, releasing arachidonic acid and lysophosphatidic acid. Upon downstream modification by cyclooxygenases or lipoxygenases, arachidonic acid is modified into active compounds called eicosanoids. Eicosanoids include prostaglandins and leukotrienes, which are categorized as anti-inflammatory and inflammatory mediators. PLA2 enzymes are commonly found in mammalian tissues as well as arachnid, insect, and snake venom. Venom from bees is largely composed of melittin, which is a stimulant of PLA2. Due to the increased presenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three-finger Toxin
Three-finger toxins (abbreviated 3FTx) are a protein superfamily of small toxin proteins found in the venom of snakes. Three-finger toxins are in turn members of a larger superfamily of three-finger protein domains which includes non-toxic proteins that share a similar protein fold. The group is named for its common structure consisting of three beta strand loops connected to a central core containing four conserved disulfide bonds. The 3FP protein domain has no enzymatic activity and is typically between 60-74 amino acid residues long. Despite their conserved structure, three-finger toxin proteins have a wide range of pharmacological effects. Most members of the family are neurotoxins that act on cholinergic intercellular signaling; the alpha-neurotoxin family interacts with muscle nicotinic acetylcholine receptors (nAChRs), the kappa-bungarotoxin family with neuronal nAChRs, and muscarinic toxins with muscarinic acetylcholine receptors (mAChRs). Structure The three-finger t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuromuscular
A neuromuscular junction (or myoneural junction) is a chemical synapse between a motor neuron and a muscle fiber. It allows the motor neuron to transmit a signal to the muscle fiber, causing muscle contraction. Muscles require innervation to function—and even just to maintain muscle tone, avoiding atrophy. In the neuromuscular system nerves from the central nervous system and the peripheral nervous system are linked and work together with muscles. Synaptic transmission at the neuromuscular junction begins when an action potential reaches the presynaptic terminal of a motor neuron, which activates voltage-gated calcium channels to allow calcium ions to enter the neuron. Calcium ions bind to sensor proteins (synaptotagmins) on synaptic vesicles, triggering vesicle fusion with the cell membrane and subsequent neurotransmitter release from the motor neuron into the synaptic cleft. In vertebrates, motor neurons release acetylcholine (ACh), a small molecule neurotransmitter, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oviparous
Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and monotremes. In traditional usage, most insects (one being ''Culex pipiens'', or the common house mosquito), molluscs, and arachnids are also described as oviparous. Modes of reproduction The traditional modes of reproduction include oviparity, taken to be the ancestral condition, traditionally where either unfertilised oocytes or fertilised eggs are spawned, and viviparity traditionally including any mechanism where young are born live, or where the development of the young is supported by either parent in or on any part of their body. However, the biologist Thierry Lodé recently divided the traditional category of oviparous reproduction into two modes that he named ovuliparity and (true) oviparity respectively. He distinguished the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
