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Echiichthys Vipera
The lesser weever (''Echiichthys vipera'') is a venomous weever of the family Trachinidae, in the order Perciformes, and the class Actinopterygii. It is generally found on the sandy sea beds of the open sea, near the shore. Lesser weevers may sting swimmers badly if disturbed in the water, and fishermen when they clean their fishing nets. The lesser weever grows up to 18 cm long, but generally less than 15 cm, with an elongated body. Its color can be described as greyish-brown on the back and silvery-white on the sides. It has no spines in front of its eyes. Habitat Lesser weever fish occur in the eastern Atlantic from the North Sea around the British Isles to Morocco and Madeira, and in the Mediterranean. It is typically found resting on the bottom, partially buried with its eyes and tip of the first dorsal fin exposed. Biology The lesser weever is littoral and benthic, living on sandy, muddy bottoms, ranging from a few meters deep to 150 m (in winter). Resting on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pieter Bleeker
Pieter Bleeker (10 July 1819 – 24 January 1878) was a Dutch medical doctor, ichthyologist, and herpetologist. He was famous for the ''Atlas Ichthyologique des Indes Orientales Néêrlandaises'', his monumental work on the fishes of East Asia published between 1862 and 1877. Life and work Bleeker was born on 10 July 1819 in Zaandam. He was employed as a medical officer in the Royal Netherlands East Indies Army from 1842 to 1860, (in French). stationed in the Dutch East Indies (now Indonesia). During that time, he did most of his ichthyology work, besides his duties in the army. He acquired many of his specimens from local fishermen, but he also built up an extended network of contacts who would send him specimens from various government outposts throughout the islands. During his time in Indonesia, he collected well over 12,000 specimens, many of which currently reside at the Naturalis Biodiversity Center in Leiden. Bleeker corresponded with Auguste Duméril of Paris. His wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Littoral
The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal areas that are permanently underwater, submerged — known as the ''foreshore'' — and the terms are often used interchangeably. However, the geographical meaning of ''littoral zone'' extends well beyond the intertidal zone to include all neritic waters within the bounds of continental shelves. Etymology The word ''littoral'' may be used both as a noun and as an adjective. It derives from the Latin language, Latin noun ''litus, litoris'', meaning "shore". (The doubled ''t'' is a late-medieval innovation, and the word is sometimes seen in the more classical-looking spelling ''litoral''.) Description The term has no single definition. What is regarded as the full extent of the littoral zone, and the way the littoral zone is divided into subregi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pain And Nociception
Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage." In medical diagnosis, pain is regarded as a symptom of an underlying condition. Pain motivates the individual to withdraw from damaging situations, to protect a damaged body part while it heals, and to avoid similar experiences in the future. Most pain resolves once the noxious stimulus is removed and the body has healed, but it may persist despite removal of the stimulus and apparent healing of the body. Sometimes pain arises in the absence of any detectable stimulus, damage or disease. Pain is the most common reason for physician consultation in most developed countries. It is a major symptom in many medical conditions, and can interfere with a person's quality of life and general functioning. Simple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stinger
A stinger (or sting) is a sharp organ found in various animals (typically insects and other arthropods) capable of injecting venom, usually by piercing the epidermis of another animal. An insect sting is complicated by its introduction of venom, although not all stings are venomous. Bites, which can introduce saliva as well as additional pathogens and diseases, are often confused with stings, and vice versa. Specific components of venom are believed to give rise to an allergic reaction, which in turn produces skin lesions that may vary from a small itching weal, or slightly elevated area of the skin, to large areas of inflamed skin covered by vesicles and crusted lesions. Stinging insects produce a painful swelling of the skin, the severity of the lesion varying according to the location of the sting, the identity of the insect and the sensitivity of the subject. Many species of bees and wasps have two poison glands, one gland secreting a toxin in which formic acid is one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WeeverFish
Weevers (or weeverfish) are nine extant species of fishes of family Trachinidae, order Trachiniformes, part of the Percomorpha clade. They are long (up to 37 cm), mainly brown in color, and have venomous spines on their first dorsal fin and gills. During the day, weevers bury themselves in sand, just showing their eyes, and snatch prey as it comes past, which consists of shrimp and small fish. Weevers are unusual in not having swim bladders, as do most bony fish, and as a result, sink as soon as they stop actively swimming. With the exception of '' T. cornutus'' from the southeast Pacific, all species in this family are restricted to the eastern Atlantic (including the Mediterranean). A tenth, extinct species, ''Callipterus speciosus'', is known from the Monte Bolca lagerstätte of the Lutetian epoch. Weevers are sometimes used as an ingredient in the recipe for ''bouillabaisse''. Weevers are sometimes erroneously called 'weaver fish', although the word is unrelated. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histamine
Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Since histamine was discovered in 1910, it has been considered a local hormone (autocoid) because it lacks the classic endocrine glands to secrete it; however, in recent years, histamine has been recognized as a central neurotransmitter. Histamine is involved in the inflammatory response and has a central role as a mediator of itching. As part of an immune response to foreign pathogens, histamine is produced by basophils and by mast cells found in nearby connective tissues. Histamine increases the permeability of the capillaries to white blood cells and some proteins, to allow them to engage pathogens in the infected tissues. It consists of an imidazole ring attached to an ethylamine chain; under physiological conditions, the amino group of the side-chain is protonate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vasoconstriction. Approximately 90% of the serotonin that the body produces is in the intestinal tract. Biochemically, the indoleamine molecule derives from the amino acid tryptophan, via the (rate-limiting) hydroxylation of the 5 position on the ring (forming the intermediate 5-hydroxytryptophan), and then decarboxylation to produce serotonin. Serotonin is primarily found in the enteric nervous system located in the gastrointestinal tract (GI tract). However, it is also produced in the central nervous system (CNS), specifically in the raphe nuclei located in the brainstem, Merkel cells located in the skin, pulmonary neuroendocrine cells and taste receptor cells in the tongue. Additionally, serotonin is stored in blood platelets and is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytolysin
Cytolysin refers to the substance secreted by microorganisms, plants or animals that is specifically toxic to individual cells, in many cases causing their dissolution through lysis. Cytolysins that have a specific action for certain cells are named accordingly. For instance, the cytolysins responsible for the destruction of red blood cells, thereby liberating hemoglobins, are named ''hemolysins'', and so on. Cytolysins may be involved in immunity as well as in venoms. Hemolysin is also used by certain bacteria, such as ''Listeria monocytogenes'', to disrupt the phagosome membrane of macrophages and escape into the cytoplasm of the cell. History and background The term "Cytolysin" or "Cytolytic toxin" was first introduced by Alan Bernheimer to describe membrane damaging toxins ( MDTs) that have cytolytic effects to cells. The first kind of cytolytic toxin discovered have hemolytic effects on erythrocytes of certain sensitive species, such as Human. For this reason "Hemolysin" wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glands
In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). Structure Development Every gland is formed by an ingrowth from an epithelial surface. This ingrowth may in the beginning possess a tubular structure, but in other instances glands may start as a solid column of cells which subsequently becomes tubulated. As growth proceeds, the column of cells may split or give off offshoots, in which case a compound gland is formed. In many glands, the number of branches is limited, in others (salivary, pancreas) a very large structure is finally formed by repeated growth and sub-division. As a rule, the branches do not unite with one another, but in one instance, the liver, this does occur when a reticulated compound gland is produced. In compound glands the more typical or secretory epithelium is found forming t ... [...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] |
