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Merkel cell

Noun 1. Oval receptor cells found in the skin of vertebrates that have synaptic contacts with somatosensory afferents. They are associated with the sense of light touch discrimination of shapes and textures. They can turn malignant and form the skin tumor known as Merkel cell carcinoma. ( 2. A cell that occurs in the basal part of the epidermis, is characterized by dense granules in its cytoplasm, is closely associated with the unmyelinated tip of a nerve fiber, and probably functions in tactile sensory perception. ( 3. A large, pale, specialized cell with lobulated nuclei and in close apposition with a single sensory nerve ending that chiefly receives touch, pressure, and texture information and relay the information to the brain. ( Syn: Merkel-Ranvier cells Name origin: Named after Merkel Friedrich Siegmund (1845–1919), German anatomist. A professor of anatomy, Merkel produced a multivolume work on human anatomy. He also introduced the use of xylene and celloidin into histological techniques and was the first to use in anatomical illustration the now-standard color scheme: red for the arteries, blue for the veins, and yellow for the nerves. In 1880 he described the composite nervous and epithelial structures that are known as Merkel’s disks or corpuscles. The epithelial cells associated with these structures are now commonly called Merkel cells....

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/məˈtabəˌlizəm/ Noun 1. The complete set of chemical reactions that occur in living cells. ( 2. The chemical processes that occur within a living organism in order to maintain life. (Google Dictionary) 3. The organic processes (in a cell or organism) that are necessary for life. ( 4. The sum of all the physical and chemical processes by which living organized substance is produced and maintained (anabolism), and also the transformation by which energy is made available for the uses of the organism (catabolism). (Dorland’s Medical Dictionary for Health Consumers) 5. The process involving a set of chemical reactions that modifies a molecule into another for storage, or for immediate use in another reaction or as a by product. ( Word origin: From French métabolisme, from Greek metabole “a change,” from metaballein “to change,” from meta- “over” + ballein “to...

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/ˌmetəˈmôrfəsəs/ Noun, pl. metamorphoses (Biology) 1. A biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal’s body structure through cell growth and differentiation. Some insects, amphibians, molluscs, crustaceans, Cnidarians, echinoderms and tunicates undergo metamorphosis, which is usually accompanied by a change of habitat or behavior. ( 2. A change in the form and often habits of an animal after the embryonic stage during normal development. (e.g. the transformation of a caterpillar into a butterfly or a tadpole into a frog.) ( 3. A marked and more or less abrupt developmental change in the form or structure of an animal (as a butterfly or a frog) occurring subsequent to birth or hatching. ( 4. The marked and rapid transformation of a larva into an adult that occurs in some animals. ( (Pathology) 1. A change in the structure of a specific body tissue. Usually degenerative. ( (Other definitions) 1. A transformation, such as that of magic or by sorcery. ( 2. A noticeable change in character, appearance, function or condition. ( Word origin: From Latin metamorphosis, from Greek metamorphosis “a transforming, a transformation,” from metamorphoun “to transform, to be transfigured,” from meta– “change” + morphe...

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