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Slit Sensilla
The slit sensilla, also known as the slit sense organ, is a small mechanoreceptory organ or group of organs in the exoskeleton of arachnids which detects physical deformation or strain due to forces experienced by the animal. The organ appears in the vast majority of discovered arachnids, and is "remarkably consistent" in location and direction within each order. The arachnid slit sensilla corresponds to the campaniform sensilla found in insects. Slit sensilla tend to be widely distributed over the arachnid's exoskeleton, but have also been found to be grouped at specific locations and in a bundle of parallel lines; the latter distribution is referred to as a "lyriform organ". The term "lyriform organ" comes from the shape of such grouped slit sensilla, which resembles a lyre. Arachnids with lyriform slit sensilla are commonly used as experimental subjects for investigations into mechanosensation because the almost 2D structure of their slit sensilla allows for relatively simple u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanoreceptory
A mechanoreceptor, also called mechanoceptor, is a sensory receptor that responds to mechanical pressure or distortion. Mechanoreceptors are located on sensory neurons that convert mechanical pressure into electrical signals that, in animals, are sent to the central nervous system. Vertebrate mechanoreceptors Cutaneous mechanoreceptors Cutaneous mechanoreceptors respond to mechanical stimuli that result from physical interaction, including pressure and vibration. They are located in the skin, like other cutaneous receptors. They are all innervated by Aβ fibers, except the mechanorecepting free nerve endings, which are innervated by Aδ fibers. Cutaneous mechanoreceptors can be categorized by what kind of sensation they perceive, by the rate of adaptation, and by morphology. Furthermore, each has a different receptive field. By sensation * The Slowly Adapting type 1 (SA1) mechanoreceptor, with the Merkel corpuscle end-organ (also known as Merkel discs) detect sustained p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exoskeleton
An exoskeleton () . is a skeleton that is on the exterior of an animal in the form of hardened integument, which both supports the body's shape and protects the internal organs, in contrast to an internal endoskeleton (e.g. human skeleton, that of a human) which is enclosed underneath other soft tissues. Some large, hard and non-flexible protective exoskeletons are known as mollusc shell, shell or armour (anatomy), armour. Examples of exoskeletons in animals include the arthropod exoskeleton, cuticle skeletons shared by arthropods (insects, chelicerates, myriapods and crustaceans) and tardigrades, as well as the corallite, skeletal cups formed by hardened secretion of stony corals, the test (biology), test/tunic of sea squirts and sea urchins, and the prominent mollusc shell shared by snails, bivalvia, clams, tusk shells, chitons and nautilus. Some vertebrate animals, such as the turtle, have both an endoskeleton and a turtle shell, protective exoskeleton. Role Exoskeletons c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachnid
Arachnids are arthropods in the Class (biology), class Arachnida () of the subphylum Chelicerata. Arachnida includes, among others, spiders, scorpions, ticks, mites, pseudoscorpions, opiliones, harvestmen, Solifugae, camel spiders, Amblypygi, whip spiders and Uropygi, vinegaroons. Adult arachnids have eight Arthropod leg, legs attached to the cephalothorax. In some species the frontmost pair of legs has converted to a sensory function, while in others, different appendages can grow large enough to take on the appearance of extra pairs of legs. Almost all Extant taxon, extant arachnids are terrestrial animal, terrestrial, living mainly on land. However, some inhabit freshwater environments and, with the exception of the pelagic zone, marine environments as well. They comprise over 110,000 named species, of which 51,000 are species of spiders. The term is derived from the Ancient Greek, Greek word (''aráchnē'', 'spider'), from the myth of the hubristic human weaver Arachne, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deformation (mechanics)
In physics and continuum mechanics, deformation is the change in the shape (geometry), shape or size of an object. It has dimension (physics), dimension of length with SI unit of metre (m). It is quantified as the residual displacement (geometry), displacement of particles in a non-rigid body, from an configuration to a configuration, excluding the body's average translation (physics), translation and rotation (its rigid transformation). A ''configuration'' is a set containing the position (geometry), positions of all particles of the body. A deformation can occur because of structural load, external loads, intrinsic activity (e.g. muscle contraction), body forces (such as gravity or electromagnetic forces), or changes in temperature, moisture content, or chemical reactions, etc. In a continuous body, a ''deformation field'' results from a Stress (physics), stress field due to applied forces or because of some changes in the conditions of the body. The relation between stre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. For some groups of organisms, their orders may follow consist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campaniform Sensilla
Campaniform sensilla are a class of mechanoreceptors found in insects, which respond to local stress and strain within the animal's cuticle. Campaniform sensilla function as Proprioception, proprioceptors that detect mechanical load as resistance to muscle contraction, similar to mammalian Golgi tendon organs. Sensory feedback from campaniform sensilla is integrated in the control of posture and locomotion. Structure Each campaniform sensillum consists of a flexible dome, which is embedded in a spongy socket within the cuticle and innervated by the dendrites of a single bipolar sensory neuron (see schematic cross-section). Campaniform sensilla are often oval-shaped with long axes of about 5-10 μm (see SEM). Campaniform sensilla are distributed across the body surface of many insects. The fruit fly ''Drosophila melanogaster'', for example, has over 680 sensilla. Campaniform sensilla are located in regions where stress is likely to be high, including on the legs, antennae, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyre
The lyre () (from Greek λύρα and Latin ''lyra)'' is a string instrument, stringed musical instrument that is classified by Hornbostel–Sachs as a member of the History of lute-family instruments, lute family of instruments. In organology, a lyre is considered a yoke lute, since it is a lute in which the strings are attached to a yoke that lies in the same plane as the sound table, and consists of two arms and a crossbar. The lyre has its origins in ancient history. Lyres were used in several ancient cultures surrounding the Mediterranean Sea. The earliest known examples of the lyre have been recovered at archeological sites that date to c. 2700 BCE in Mesopotamia. The oldest lyres from the Fertile Crescent are known as the eastern lyres and are distinguished from other ancient lyres by their flat base. They have been found at archaeological sites in Egypt, Syria, Anatolia, and the Levant. In a discussion of the Nubian lyre, Carl Engel notes that modern Egyptians call it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanosensation
Mechanosensation is the transduction of mechanical stimuli into neural signals. Mechanosensation provides the basis for the senses of light touch, hearing, proprioception, and pain. Mechanoreceptors found in the skin, called cutaneous mechanoreceptors, are responsible for the sense of touch. Tiny cells in the inner ear, called hair cells, are responsible for hearing and balance. States of neuropathic pain, such as hyperalgesia and allodynia, are also directly related to mechanosensation. A wide array of elements are involved in the process of mechanosensation, many of which are still not fully understood. Cutaneous mechanoreceptors Cutaneous mechanoreceptors are physiologically classified with respect to conduction velocity, which is directly related to the diameter and myelination of the axon. Rapidly adapting and slowly adapting mechanoreceptors Mechanoreceptors that possess a large diameter and high myelination are called ''low-threshold mechanoreceptors''. Fibers that respond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrostimulation
Electro-stimulation is stimulation using electricity. It can be used in the context of: * Animal husbandry as part of the artificial insemination Artificial insemination is the deliberate introduction of sperm into a female's cervix or uterine cavity for the purpose of achieving a pregnancy through in vivo fertilization by means other than sexual intercourse. It is a fertility treatment ... process * Bioelectromagnetics ** Cranial electrotherapy stimulation ** Transcranial magnetic stimulation ** Transcorneal electrical stimulation * Electrical muscle stimulation ** Bio-electric stimulation therapy ** Functional electrical stimulation ** Erotic electrostimulation, sometimes a form of BDSM {{SIA Neurotechnology Former disambiguation pages converted to set index articles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chitin
Chitin (carbon, C8hydrogen, H13oxygen, O5nitrogen, N)n ( ) is a long-chain polymer of N-Acetylglucosamine, ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chitin are produced each year in the biosphere. It is a primary component of cell walls in fungi (especially filamentous and mushroom-forming fungi), the exoskeletons of arthropods such as crustaceans and insects, the radulae, cephalopod beaks and Gladius (cephalopod), gladii of molluscs and in some nematodes and diatoms. It is also synthesised by at least some fish and lissamphibians. Commercially, chitin is extracted from the shells of crabs, shrimps, shellfish and lobsters, which are major by-products of the seafood industry. The structure of chitin is comparable to cellulose, forming crystalline nanofibrils or whiskers. It is functionally comparable to the protein keratin. Chitin has proved useful ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spider Anatomy
The anatomy of spiders includes many characteristics shared with other arachnids. These characteristics include bodies divided into two tagmata (sections or segments), eight jointed legs, no wings or antennae, the presence of chelicerae and pedipalps, simple eyes, and an exoskeleton, which is periodically shed. Spiders also have several adaptations that distinguish them from other arachnids. All spiders are capable of producing silk of various types, which many species use to build webs to ensnare prey. Most spiders possess venom, which is injected into prey (or defensively, when the spider feels threatened) through the fangs of the chelicerae. Male spiders have specialized pedipalps that are used to transfer sperm to the female during mating. Many species of spiders exhibit a great deal of sexual dimorphism. External anatomy Spiders, unlike insects, have only two main body parts ( tagmata) instead of three: a fused head and thorax (called a cephalothorax or prosoma) and an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
