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secretion
se·cre·tion 1 S0206900 (sĭ-krē′shən)n.1. The process of secreting a substance, especially one that is not a waste, from the blood or cells: secretion of hormones; secretion of milk by the mammary glands.2. A substance, such as saliva, mucus, tears, bile, or a hormone, that is secreted.
[French sécrétion, from Old French, separation, from Latin sēcrētiō, sēcrētiōn-, from sēcrētus, past participle of sēcernere, to set aside; see secern.]
se·cre′tion·ar′y (-shə-nĕr′ē) adj.
se·cre·tion 2 S0206900 (sĭ-krē′shən)n.1. The act of concealing something in a hiding place.2. The act of stealing something secretly.
[From secrete.]secretion (sɪˈkriːʃən) n1. (Biology) a substance that is released from a cell, esp a glandular cell, and is synthesized in the cell2. (Biology) the process involved in producing and releasing such a substance from the cell[C17: from Medieval Latin sēcrētiō, from Latin: a separation; see secern] seˈcretionary adjse•cre•tion (sɪˈkri ʃən)
n. 1. (in a cell or gland) the process of separating, elaborating, and releasing a substance that fulfills some function within the organism or undergoes excretion. 2. the product of this process. [1640–50; < Latin sēcrētiō separation, derivative of sēcrē-, variant s. of sēcernere (see secern)] se•cre′tion•ar`y (-ʃəˌnɛr i) adj. secretion- gall - As in gallbladder, it refers to a secretion of the liver or to bile.
- honeyflow - The period of secretion of honey or nectar by flowers.
- sepia - A cuttlefish, the origin of the brown pigment prepared from a secretion of the fish.
- larp - The secretion from eucalyptus.
secretionThe natural production and release of a useful substance.Thesaurus| Noun | 1. | secretion - the organic process of synthesizing and releasing some substancesecernmentgalactosis - the secretion of milkhypersecretion - excessive secretionbiological process, organic process - a process occurring in living organismssalivation - the secretion of saliva | | 2. | secretion - a functionally specialized substance (especially one that is not a waste) released from a gland or cellganoin, ganoine - shiny substance that resemble enamel and is secreted by the corium of certain fishes (especially ganoid fishes) and composes the outer layer of their scalesbodily fluid, body fluid, liquid body substance, humour, humor - the liquid parts of the bodylachrymal secretion, lacrimal secretion - saline fluid secreted by lacrimal glands; lubricates the surface of the eyeballperspiration, sudor, sweat - salty fluid secreted by sweat glands; "sweat poured off his brow"endocrine, hormone, internal secretion - the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effectintestinal juice - secretions by glands lining the walls of the intestinesautacoid, autocoid - any physiologically active internal secretion especially one of uncertain classificationsynovia, synovial fluid - viscid lubricating fluid secreted by the membrane lining joints and tendon sheaths etc.mucous secretion, mucus - protective secretion of the mucus membranes; in the gut it lubricates the passage of food and protects the epithelial cells; in the nose and throat and lungs it can make it difficult for bacteria to penetrate the body through the epitheliumsaliva, spittle, spit - a clear liquid secreted into the mouth by the salivary glands and mucous glands of the mouth; moistens the mouth and starts the digestion of starchessebum - the oily secretion of the sebaceous glands; with perspiration it moistens and protects the skinroyal jelly - a secretion of the pharyngeal glands of bees that is fed to very young larvae and to bees destined to be queensmusk - an odorous glandular secretion from the male musk deer; used as a perfume fixativenectar - a sweet liquid secretion that is attractive to pollinatorspheromone - a chemical substance secreted externally by some animals (especially insects) that influences the physiology or behavior of other animals of the same species |
secretionnoun discharge, emission, excretion, exudation, extravasation (Medical) the secretion of adrenalineTranslationssecrete (siˈkriːt) verb1. (of a gland or similar organ of the body) to separate (a fluid) from the blood, store it, and give it out. The liver secretes bile. 分泌 分泌2. to hide. He secreted the money under his mattress. 隱藏 隐藏seˈcretion (-ʃən) noun1. the process of secreting a fluid. 分泌 分泌2. a substance produced by this process. Saliva and urine are secretions. 分泌液 分泌液Secretion
secretion, in biology, substance elaborated by the living material of an animal or plant. Secretions in humans can be produced by a single cell or by a group of cells commonly called a gland. Some secretions perform special functions in the body (true secretions); others are eliminated as waste products (excretions). Digestive secretions include saliva, gastric juice, intestinal juice, pancreatic juice, and bile. Certain secretions serve as lubricants, e.g., the synovial fluid in joints or the secretions from mucous membranes and from the lachrymal (tear) glands. The mammary glands secrete milk. The endocrine (ductless) glands secrete hormones that enter directly into the bloodstream (see glandgland,
organ that manufactures chemical substances. A gland may vary from a single cell to a complex system of tubes that unite and open onto a surface through a duct. The endocrine glands, e.g.
..... Click the link for more information. ). Among the excretions from the body are urine (from the kidneys), perspiration (from the sweat glands), and bile pigments (from the gall bladder). Plant secretions include nectar and various enzymes concerned with the digestion of nutrients within the plant cells.Secretion The export of proteins by cells. With few exceptions, in eukaryotic cells proteins are exported via the secretory pathway, which includes the endoplasmic reticulum and the Golgi apparatus. Secreted proteins are important in many physiological processes, from the transport of lipids and nutrients in the blood, to the digestion of food in the intestine, to the regulation of metabolic processes by hormones. See Cell (biology), Cell organization Proteins destined for export are synthesized on ribosomes attached to the outside of the rough endoplasmic reticulum, a portion of the endoplasmic reticulum that is specialized for the synthesis of secretory proteins and most of the cell's membrane proteins. After they are folded, the proteins enter small vesicles in which they are transported to the Golgi apparatus. When the proteins reach the last cisterna of the Golgi, a highly tubulated region known as the trans-Golgi network, they are sorted and packaged again into transport vesicles, some of which are in the form of elongated tubules. From here, there are two pathways that proteins can take to the cell surface, depending on the cell type. Proteins can be transported directly to the plasma membrane (constitutive secretion) or to secretory granules (regulated secretion). See Endoplasmic reticulum, Golgi apparatus In all cells, there exists a constitutive secretion pathway whereby vesicles and tubules emerging from the trans-Golgi network fuse rapidly with the plasma membrane. The emerging vesicles and tubules attach to microtubules, cytoskeletal elements emanating from the Golgi region, that accelerate their transport to the plasma membrane. See Absorption (biology), Cell membranes In cells that secrete large amounts of hormones or digestive enzymes, most secretory and membrane proteins emerging from the trans-Golgi network are not immediately secreted, but are stored in membrane-bounded secretory granules. Secretory granules release their contents into the extracellular space in a process known as exocytosis, when their membranes fuse with the plasma membrane. Exocytosis occurs only after the cell receives a signal, usually initiated by the binding of a hormone or neurotransmitter to a receptor on the cell surface. The receptor triggers a signal transduction cascade that results in increased concentrations of second messengers such as cyclic adenosine 3′, 5′-monophosphate and phosphatidylinositol triphosphate. In most secretory cells, the second messengers or the hormone receptors themselves trigger the opening of calcium channels through which calcium ions stream into the cytoplasm. Calcium initiates the docking of the secretory granules with the plasma membrane and the activation of the fusion apparatus. See Enzyme, Hormone, Signal transduction In exceptional cases, proteins can be exported directly from the cytoplasm without using the secretory pathway. One such protein is fibroblast growth factor, a hormone involved in the growth and development of tissues such as bone and endothelium. Several interleukins, proteins that regulate the immune response, are also released via an unconventional route that may involve transport across the plasma membrane through channel proteins. These channels have adenosine 5′-triphosphatase (ATPase) enzyme activity and use the energy derived from the hydrolysis of ATP to catalyze transport. See Cellular immunology Secretion a substance elaborated and released by animal and human glands. According to their physiological function, secretory products are grouped as secretions proper, excretions, or incretions (hormones). In the narrow sense of the word, a secretion is a substance needed for the performance of an organism’s normal vital activities. Some secretions, for example, digestive enzymes, cause the chemical alteration of the environment, whereas other secretions, including mucus and cutaneous sebum, cover the external surface of the body with a layer that protects the body against the external environment. Hormones, a third group of secretions, are released into the body, where they are conveyed by the bloodstream and exert a regulatory influence (excitatory or inhibitory) on other bodily functions or systems. A fourth group of secretions consists of food products, including milk. Secretions may also include pheromones, which are substances released by the glands of some animals into the external environment, where they serve to regulate or sexually attract other individuals of the same species and sometimes of other species. Excretions are substances formed as the end products of dissimilation and must be removed from the organism as quickly as possible. Chemically, most secretions are proteins, polysaccharides, or glycoproteins. Some glands secrete lipids, including steroids. B. V. ALESHIN
Secretion the elaboration and release of secretions by glandular cells. While performing its vital activities, every cell of an organism forms several metabolic products, releasing them either into the external or internal environment. When the secretory function is the basic function of a group of specialized glandular cells it is called secretion. External, or exocrine, secretion is distinguished from internal, or endocrine, secretion. In external secretion the products elaborated by a gland are released into the external environment; the secretion first enters the glandular duct, from which it is discharged onto the surface of the body or into hollow organs. In internal secretion (incretion) synthesized substances are released into the blood or lymph. The secretory cycle of any gland has both a production (biosynthesis) phase and a release phase. The term “secretion” is sometimes applied only to the latter phase. In some glands the phases occur simultaneously; the phases occur at different times in glands whose phases are regulated by different specific mechanisms. The secretion process resembles an intracellular conveyor system, in which the synthesized product gradually matures and steadily moves with the cell from one organoid to another. The initial products, including amino acids, monosaccharides, fatty acids, and salts, are absorbed from the blood and tissue fluid by a glandular cell. The biosynthesis of the secretion (especially of protein products) starts in the endoplasmic reticulum, where the amino acids, which have been adsorbed on the cellular membranes, are joined together in a sequence determined by the messenger RNA of ribosomes. The synthesized initial product accumulates in the fissures and lacunae of the endoplasmic reticulum, from which it shifts to the area of the laminar Golgi complex, where the maturation of a secretion is completed. In the area of the Golgi complex in some glandular cells the synthesized protein combines with carbohydrates and the secretion is converted into a glycoprotein. Mitochondria, which are numerous in glandular cells, produce the energy needed to synthesize and release a secretion. The synthesis of secretions of a lipidic (steroid) nature is completed on the mitochondria. In the phase of secretion release increases are observed in oxygen consumption by the glandular cells, intracellular osmotic pressure, and the amount of water entering the cells. The result is the establishment in a glandular cell of a stream of water, which enters through the base of the cell and emerges through the apical membrane. Flowing through the cytoplasm, the water picks up the accumulated secretion and releases it from the cell, either in the form of a solution that is diffused through the apical membrane or in the form of drops that are passed through membrane pores. During this type of secretion, which is called merocrine secretion, glandular cells do not suffer any damage. If, however, the secretion is insoluble in water or for some other reason is incapable of passing through the apical membrane, the intensified passing of water into a swelling glandular cell causes the apex of the cell with its accumulated granules or drops of secretion to swell clavately and then rupture or be detached. The liberation of secretion by the detachment of the apex of a glandular cell without the cell’s destruction is called apocrine secretion. Sometimes this type of secretion is limited to the swelling and detachment of microvilli from a glandular cell (microapocrine secretion). Occasionally, while a glandular cell is degenerating, it is completely transformed into a drop of secretion and is ejected from the epithelial layer into the lumen of the gland; this type of secretion is called holocrine secretion. In the course of evolution, holocrine secretion, which is a primitive type of secretion, has been replaced by merocrine secretion, which is more effective. Both phases of the secretory cycle are regulated by the combined or successive influences of several neural and humoral factors. The nerve fibers that carry impulses stimulating secretion to the glands are called secretory fibers. The neural effects that are manifested by the intensified elaboration of secretion during the production phase are called trophic effects. There is no clear distinction between secretory and trophic nerves because the stimulation of a fiber that innervates a gland causes both secretory and trophic effects. Glandular activity is also influenced by humoral agents, including some hormones (especially those involved in regulating the functions of the endocrine glands). For example, the thyrotropic, gonadotropic, and adrenocorticotropic hormones of the anterior pituitary excite, respectively, the thyroid gland, the ovaries and testes, and the adrenal cortex (the glucocorticoid function). Secretin, which is produced in the duodenal mucosa, stimulates the release of pancreatic juice by the acinar cells of the pancreas. Besides hormones, other substances formed in the body may also affect glandular function. Histamine, for example, sharply intensifies the secretion of the fundic glands of the stomach. The effect of humoral stimulants is manifested in both phases of the secretory cycle. Certain ions directly affect the secretion of many glands; an excess of monovalent cations (K+ or Na+) usually intensifies secretion, whereas bivalent ions (Ca2+ and Mg2+) weaken secretion. The stimulation of a glandular cell is based on the activation of adenyl cyclase, an enzyme localized in the cell’s surface membrane. Adenyl cyclase acts as a stimulus in the formation of cyclic adenosine monophosphate, which regulates the chain of intracellular reactions resulting in the increased activity of the specific enzyme systems causing secretion. The large number of factors influencing secretion is explained by the fact that they are all equally capable of activating the adenyl-cyclase mechanism of the glandular cell. Nerve cells are also characterized by secretory activity; they all elaborate and release mediators, and in neurosecretory cells the production of physiologically active substances called neurohormones reaches a high level of intensity. REFERENCESKoshtoiants, Kh. S. Osnovy sravnitel’noi fiziologii, 2nd ed., vol. 1. Moscow-Leningrad, 1950.
Babkin, B. P. Sekretornyi mekhanizm pishchevaritel’nykh zhelez. Leningrad, 1960. (Translated from English.)
Khirsh, G. “O printsipe ‘konveiera’ v vyrabotke fermentov ekzokrinnymi kletkami podzheludochnoi zhelezy.” In Funktsional’naia morfologiia kletki. Moscow, 1963.
Brodskii, V. Ia. Trofika kletki. Moscow, 1966.
Shubnikova, E. A.“Sekretornaia deiatel’nost’.” In Rukovodstvo po tsitologii, vol. 2. Moscow-Leningrad, 1966.
Shubnikova, E. A. Tsilologiia i tsitofiziologiia sekretornogo protsessa. Moscow, 1967.
DeRobertis, E., W. Nowinski, and F. Saez. Biologiia kletki. Moscow, 1973. (Translated from English.)
Yost, H. Fiziologiia kletki. Moscow, 1975. (Translated from English.)
Caro, L. G., and G. E. Palade. “Protein Synthesis, Storage and Discharge in the Pancreatic Exocrine Cell.” Journal of Cell Biology, 1964, vol. 20. no. 3.
Kurosumi, K. “Electron Microscopic Analysis of the Secretion Mechanism.” International Review of Cytology, 1961, vol. 11.B. V. ALESHIN
Secretion a round mineral aggregate that forms when a crystalline or colloidal substance fills cavities in rocks. The characteristic feature of many secretions is a sequential, concentrically layered deposition of the mineral substance from the walls of the cavity toward the center. The separate layers frequently differ in color or composition. Small cavities are usually completely filled with the mineral substance. Sometimes the central part of a secretion has radial-filamented aggregates of some mineral, such as zeolite. In the center of large cavities a small empty space is often found with walls covered by druses of crystals or sinter formations. Small secretions, measuring up to 10 mm across, are called amygdules, and large ones, geodes. The formation of secretions is usually linked with hydrothermal or supergene processes. secretion[si′krē·shən] (geology) A secondary structure formed of material deposited (from solution) within an empty cavity in any rock, especially a deposit formed on or parallel to the walls of the cavity, the first layer being the outer one. (physiology) The act or process of producing a substance which is specialized to perform a certain function within the organism or is excreted from the body. The material produced by such a process. secretion1. a substance that is released from a cell, esp a glandular cell, and is synthesized in the cell 2. the process involved in producing and releasing such a substance from the cell secretion
secretion [se-kre´shun] 1. the cellular process of elaborating a specific product. This activity may range from separating a specific substance of the blood to the elaboration of a new chemical substance.2. material that is secreted, such as sebum (the fatty substance produced by the sebaceous glands to lubricate the skin), saliva (produced by the salivary glands), and gastric juice (secreted by specialized glands of the stomach). The secretions of the endocrine glands include various hormones and are important in the overall regulation of body processes.se·cre·tion (se-krē'shŭn), 1. Production by a cell or aggregation of cells (a gland) of a physiologically active substance and its movement out of the cell or organ in which it is formed. 2. The solid, liquid, or gaseous product of cellular or glandular activity that is stored in or used by the organism in which it is produced. Compare: excretion. [L. secerno, pp. -cretus, to separate] secretion (sĭ-krē′shən)n.1. The process of secreting a substance, especially one that is not a waste, from the blood or cells: secretion of hormones; secretion of milk by the mammary glands.2. A substance, such as saliva, mucus, tears, bile, or a hormone, that is secreted.
se·cre′tion·ar′y (-shə-nĕr′ē) adj.se·cre·tion (sĕ-krē'shŭn) 1. Production by a cell or by an aggregation of cells (a gland) of a physiologically active substance and its movement out of the cell or organ in which it is formed. 2. The solid, liquid, or gaseous product of cellular or glandular activity that is stored up in or used by the organism in which it is produced.
Compare: excretion[L. se-cerno, pp. -cretus, to separate]secretion The synthesis and release of chemical substances by cells or glands. Substances secreted include enzymes, hormones, lubricants, surfactants and neurotransmitters. Internal secretion is secretion into the bloodstream. External secretion may be into the intestinal canal or other organs or on to the skin. Compare EXCRETION.secretion - the process by which a useful substance produced in a cell is passed through the plasma membrane to the outside.
- the substance itself. Secretions are usually produced by gland cells, but may be the results of cell destruction as in SEBACEOUS GLANDS. Glands of internal secretion (ENDOCRINES) pass their secretions directly into the blood stream whereas glands of external secretion (EXOCRINES) pass their secretions into special ducts.
SecretionA substance, such as saliva or mucus, that is produced and given off by a cell or a gland.Mentioned in: Expectorantssecretion 1. The substance produced by a cell or organ (e.g. a gland). 2. Production by a cell or organ of a physiologically active substance. This flow out of a cell is driven by an osmotic pressure gradient across the membrane, which is created by active transport of one or more ion species from one side to the other. See active transport; ultrafiltration.se·cre·tion (sĕ-krē'shŭn) 1. Production by a cell or aggregation of cells (a gland) of a physiologically active substance and its movement out of cell or organ in which formed. 2. Solid, liquid, or gaseous product of cellular or glandular activity stored in or used by organism in which it is produced. [L. se-cerno, pp. -cretus, to separate]Patient discussion about secretionQ. What's the secret to looking good and fit? My friend who regularly visits my beauty parlor became very slim within 3 months. To be honest I am jealous of her. What's the secret to looking good and fit?A. the answer is that there is no secret. you need to be consistent with your eating and exercise. Q. how do celebrities look so thin and beautiful? what is their secret? A. and all sorts of liposuctions and esthetic surgery... More discussions about secretionsecretion
Related to secretion: tubular secretionSynonyms for secretionnoun dischargeSynonyms- discharge
- emission
- excretion
- exudation
- extravasation
Synonyms for secretionnoun the organic process of synthesizing and releasing some substanceSynonymsRelated Words- galactosis
- hypersecretion
- biological process
- organic process
- salivation
noun a functionally specialized substance (especially one that is not a waste) released from a gland or cellRelated Words- ganoin
- ganoine
- bodily fluid
- body fluid
- liquid body substance
- humour
- humor
- lachrymal secretion
- lacrimal secretion
- perspiration
- sudor
- sweat
- endocrine
- hormone
- internal secretion
- intestinal juice
- autacoid
- autocoid
- synovia
- synovial fluid
- mucous secretion
- mucus
- saliva
- spittle
- spit
- sebum
- royal jelly
- musk
- nectar
- pheromone
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