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https://www.britannica.com/science/cuttlebone
Cuttlebone
Cuttlebone …internal calcified shell called the cuttlebone. The approximately 100 species of cuttlefish range between 2.5 and 90 cm (1 to 35 inches) and have somewhat flattened bodies bordered by a pair of narrow fins. All species have eight arms and two longer tentacles that are used in capturing prey and… Cuttlefishe...
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https://www.britannica.com/science/CV-carbonaceous-chondrite
CV carbonaceous chondrite
CV carbonaceous chondrite …that it belongs to the CV group of the first table and petrologic type 3 of the second table.
017ec6e5e7aa84f17f0be5df7aea7073
https://www.britannica.com/science/cyanogen-chloride
Cyanogen chloride
Cyanogen chloride Cyanogen chloride, made by the reaction of chlorine with hydrocyanic acid or its salts, is a liquid that has been suggested for use as a military poison gas. Cyanogen bromide is formed by the reaction of bromine with salts of hydrocyanic acid; it is a…
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https://www.britannica.com/science/cyathium
Cyathium
Cyathium …are in cup-shaped clusters called cyathia, each of which seems to be a single female flower but actually consists of a single pistil surrounded by several male flowers, each of which has a single stamen. These clusters of reduced flowers are enclosed by an involucre (whorl) of bracts (modified leaves)…
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https://www.britannica.com/science/cybernetics
Cybernetics
Cybernetics Cybernetics, control theory as it is applied to complex systems. Cybernetics is associated with models in which a monitor compares what is happening to a system at various sampling times with some standard of what should be happening, and a controller adjusts the system’s behaviour accordingly. The term cy...
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https://www.britannica.com/science/cyclamate
Cyclamate
Cyclamate Cyclamate, odourless white crystalline powder that is used as a nonnutritive sweetener. The name usually denotes either calcium cyclamate or sodium cyclamate, both of which are salts of cyclohexylsulfamic acid (C6H11NHSO3H). These compounds are stable to heat and are readily soluble in water. Cyclamates have...
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https://www.britannica.com/science/cyclic-disease-transmission
Cyclic disease transmission
Cyclic disease transmission This is an example of cyclic disease transmission. The relationship between the parasitic disease organism and its two hosts, vertebrate and insect, is a result of evolutionary adaptation. However, it is not known whether the trypanosome was originally a fly parasite that spread to humans an...
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https://www.britannica.com/science/cyclical-shift-substitution-cipher
Cyclical-shift substitution cipher
Cyclical-shift substitution cipher …has discovered to his embarrassment, cyclical-shift substitution ciphers are not secure, nor is any other monoalphabetic substitution cipher in which a given plaintext symbol is always encrypted into the same ciphertext symbol. Because of the redundancy of the English language, only ...
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https://www.britannica.com/science/cyclin-dependent-kinase
Cyclin-dependent kinase
Cyclin-dependent kinase …family of key enzymes, the cyclin-dependent kinases (CDKs), which participate in many cell functions. By 2001 about a half dozen other CDKs were identified in humans.
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https://www.britannica.com/science/cyclophosphamide
Cyclophosphamide
Cyclophosphamide …are nitrogen mustards (chlorambucil and cyclophosphamide), cisplatin, nitrosoureas (carmustine, lomustine, and semustine), alkylsulfonates (busulfan), ethyleneimines (thiotepa), and triazines (dacarbazine). …or chemotherapeutic drugs, such as cyclophosphamide or methotrexate, may be used. GPA can be b...
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https://www.britannica.com/science/cylindrical-projection
Cylindrical projection
Cylindrical projection Cylindrical projection, in cartography, any of numerous map projections of the terrestrial sphere on the surface of a cylinder that is then unrolled as a plane. Originally, this and other map projections were achieved by a systematic method of drawing the Earth’s meridians and latitudes on the ...
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https://www.britannica.com/science/Cyrillid-meteor-shower
Cyrillid meteor shower
Cyrillid meteor shower The Cyrillid shower of 1913 had no radiant (the meteoroids seemed to enter the atmosphere from a circular orbit around Earth) and was named for St. Cyril of Alexandria, on whose feast day (formerly celebrated on February 9) the shower was observed. The great Leonid meteor…
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https://www.britannica.com/science/cyst
Cyst
Cyst Cyst, in biology, enclosed sac within body tissues, having a distinct membrane and generally containing a liquid material. In the life cycle of certain parasitic worms, a cyst develops around the larval form within the muscle tissue of the host animal. Although the majority of cysts are benign, several varieties...
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https://www.britannica.com/science/cysticercus
Cysticercus
Cysticercus …(encysts) and is called a cysticercus, or bladder worm. If the cysticercus is eaten alive in raw meat, it attaches itself to the host’s intestine and develops directly into a mature adult. …is the pork tapeworm larva, Cysticercus, which causes nodules in the muscle tissue and brain. The organism grows, lay...
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https://www.britannica.com/science/cystinuria
Cystinuria
Cystinuria Cystinuria, hereditary error of metabolism characterized by the excessive excretion into the urine of four amino acids: cystine, lysine, arginine, and ornithine. The main clinical problem of cystinuria is the possibility of cystine stone formation in the kidney; unlike lysine, arginine, and ornithine, whic...
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https://www.britannica.com/science/cystolith
Cystolith
Cystolith … arranged in opposite pairs, with cystoliths (enlarged cells containing crystals of calcium carbonate) in streaks or protuberances in the vegetative parts. The bisexual flowers are frequently bilaterally symmetrical and are usually enclosed by leaflike bracts, often coloured and large. Sepals and petals numb...
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https://www.britannica.com/science/cytokinesis
Cytokinesis
Cytokinesis Cytokinesis, in biology, the process by which one cell physically divides into two cells. Cytokinesis represents the major reproductive procedure of unicellular organisms, and it occurs in the process of embryonic development and tissue growth and repair of higher plants and animals. It generally follows n...
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https://www.britannica.com/science/D-lines
D-lines
D-lines D-lines, in spectroscopy, a pair of lines, characteristic of sodium, in the yellow region of the spectrum. Their separation is too small to be detected with a spectroscope of low resolving power. The line is the fourth prominent absorption line in the Sun’s spectrum, starting from the red end, and accordingly...
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https://www.britannica.com/science/dactylozooid
Dactylozooid
Dactylozooid Some colonies possess dactylozooids, tentacleless polyps heavily armed with nematocysts that seem primarily concerned with defense. Gonozooids develop reproductive structures called gonophores. Members of the order Siphonophora, free-floating colonial hydrozoans, display an even greater variety of polymorp...
c3adf913fc8bb4cb56f931af3f9b6d66
https://www.britannica.com/science/daily-reference-value
Daily reference value
Daily reference value Daily reference value (DRV), set of numerical quantities developed by the U.S. Food and Drug Administration for the dietary intake of energy-containing macronutrients, including carbohydrates, cholesterol, fat, fibre, saturated fatty acids, potassium, protein, and sodium. In the United States the...
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https://www.britannica.com/science/Dalradian-Series
Dalradian Series
Dalradian Series Dalradian Series, sequence of highly folded and metamorphosed sedimentary and volcanic rocks of late Precambrian to Early Cambrian age, about 540 million years old, that occurs in the southeastern portions of the Scottish Highlands of Great Britain, where it occupies a belt 720 kilometres (450 miles)...
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https://www.britannica.com/science/Dalton-minimum
Dalton minimum
Dalton minimum Dalton minimum, also called Modern minimum, period of reduced sunspot activity that occurred between roughly 1790 and 1830. It was named for the English meteorologist and chemist John Dalton. Sunspot activity waxes and wanes with over about an 11-year cycle. During the Dalton minimum, the solar cycle co...
a2be4e97773ccefc76d0e2695f4660d4
https://www.britannica.com/science/Daltons-law
Dalton's law
Dalton's law Dalton’s law, the statement that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the individual component gases. The partial pressure is the pressure that each gas would exert if it alone occupied the volume of the mixture at the same temperature. This empirical r...
2dc726c7c5de68b9766e35336fa214a0
https://www.britannica.com/science/damped-vibration
Damped vibration
Damped vibration The simple harmonic oscillations discussed above continue forever, at constant amplitude, oscillating as shown in Figure 3 between A and −A. Common experience indicates that real oscillators behave somewhat differently, however. Harmonic oscillations tend to die away as time goes on.…