corpusclephilosophy

• importance in atomism ( in atomism: Atoms as lumpish corpuscles )

  As corpuscles (minute particles), atoms can either be endowed with intrinsic qualities or be inherently qualityless.

  in atomism: The existence of the void )

  When in the beginning of the 19th century the corpuscular theory of light in its turn was abandoned in favour of the wave theory, the case for the existence of the void had to be reopened, for the proponents of the wave theory did not think in terms of action at a distance; the propagation of waves seemed to presuppose, instead, a medium with not only geometrical properties but with physical...

• role in endocrine system hormone

  The corpuscles of Stannius, found only in bony fishes, are sac-like bodies in the kidney. Although they were once thought to be a form of adrenocortical tissue, they differ from it in embryological origin as well as in cytological characteristics; moreover, although the corpuscles of Stannius are capable of limited steroid biosynthesis, they cannot convert cholesterol into corticoids, a process...

• function in human sensory reception ( in senses: Cutaneous (skin) senses )

  ...areas of the skin are particularly sensitive to certain modalities. The nerve endings found in skin may be either Ruffini endings, encapsulated endings, Meissner’s corpuscles, Krause end bulbs, pacinian corpuscles, and free nerve endings, all of which can respond to any one or a combination of cutaneous stimuli. Axons project from these nerve endings and form bundles (nerves) that lead to...

  in sensory reception, human: Nerve function )

  On the other hand, some tactile receptors (e.g., Pacinian corpuscles) respond only to mechanical deformation. A Pacinian corpuscle is an onion-shaped structure of nonneural (connective) tissue built up around the nerve ending that reduces the mechanical sensitivity of the nerve terminal itself. If the onionlike capsule is entirely removed, mechanical sensitivity not only remains but is somewhat...

structure of

• mechanoreception mechanoreception

  Relatively little research has been done with regard to the physiology of individual tangoreceptors in vertebrates. The Pacinian corpuscle of higher vertebrates, however, has been studied in isolation. These corpuscles, found under the skin, are scattered within the body, particularly around muscles and joints. Local pressure exerted at the surface or within the body causes deformation of parts...

• nervous system nervous system, human

  ...hair, but they rapidly adapt to continued stimulation and stop firing. In hairless skin both rapidly and slowly adapting receptors provide information about the force of mechanical stimulation. The Pacinian corpuscles, elaborate structures found in the skin of the fingers and in other organs, are layers of fluid-filled membranes forming structures just visible to the naked eye at the terminals...

• development in primates ( in primate )

  ...and as most present-day primates are arboreal, this characteristic suggests that they evolved from an ancestor that was arboreal. So too does primates’ possession of specialized nerve endings (Meissner’s corpuscles) in the hands and feet that increase tactile sensitivity. As far as is known, no other placental mammal has them. Primates possess dermatoglyphics (the skin ridges responsible...

  in primate: Touch )

  The skin of the primate hand is well adapted for tactile discrimination. Meissner’s corpuscles, the principal receptors for touch in hairless skin, are best developed in apes and humans, but they can be found in all primates. Structurally correlated with a high level of tactile sensitivity are certain anatomic features of the skin of the hands and feet, such as the absence of pads on the palms...

• function in human sensory reception ( in senses: Cutaneous (skin) senses )

  ...to temperature, pressure, and pain; different areas of the skin are particularly sensitive to certain modalities. The nerve endings found in skin may be either Ruffini endings, encapsulated endings, Meissner’s corpuscles, Krause end bulbs, pacinian corpuscles, and free nerve endings, all of which can respond to any one or a combination of cutaneous stimuli. Axons project from these nerve endings...

  in sensory reception, human: Nerve function )

  Microscopic examination of the skin reveals a variety of nerve terminals including free nerve endings (which are most common), Ruffini endings, and encapsulated endings, such Pacinian corpuscles, Meissner’s corpuscles, and Krause end...

• function of eye eye, human

  The stroma appears as a set of lamellae, or plates, running parallel with the surface and superimposed on each other like the leaves of a book; between the lamellae lie the corneal corpuscles, cells that synthesize new collagen (connective tissue protein) essential for the repair and maintenance of this layer. The lamellae are made up of microscopically visible fibres that run parallel to form...