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tropics

(Encyclopedia)tropics, also called tropical zone or torrid zone, all the land and water of the earth situated between the Tropic of Cancer at lat. 231⁄2°N and the Tropic of Capricorn at lat. 231⁄2°S. Every po...

fermentation

(Encyclopedia)fermentation, process by which the living cell is able to obtain energy through the breakdown of glucose and other simple sugar molecules without requiring oxygen. Fermentation is achieved by somewhat...

nitrate

(Encyclopedia)nitrate, chemical compound containing the nitrate (NO3) radical. Nitrates are salts or esters of nitric acid, HNO3, formed by replacing the hydrogen with a metal (e.g., sodium or potassium) or a radic...

benzene, 1,2,3-trihydroxy-

(Encyclopedia)benzene, 1,2,3-trihydroxy-, IUPAC name for pyrogallol. See gallic acid. ...

mutation

(Encyclopedia)mutation, in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any change in the delica...

isoniazid

(Encyclopedia)isoniazid īˌsōnīˈəzĭd [key], drug used to treat tuberculosis. Also known as isonicotinic acid hydrazide, isoniazid is the most effective antituberculosis drug currently available. The drug inhi...

triglyceride

(Encyclopedia)triglyceride, ester formed from glycerol and one to three fatty acids. Fats and oils are triglycerides. In a simple triglyceride such as palmitin or stearin, all three fatty-acid groups are identical....

sodium sulfate

(Encyclopedia)sodium sulfate, chemical compound, Na2SO4. It is a white, orthorhombic crystalline compound at ordinary temperatures; above 100℃ it assumes a monoclinic structure, and above about 250℃ it assumes ...

pickle

(Encyclopedia)pickle, general term for fruits or vegetables preserved in vinegar or brine, usually with spices or sugar or both. Vegetables commonly pickled include the beet, cabbage, cauliflower, cucumber, olive, ...

Namib

(Encyclopedia)Namib näˈmĭb [key], desert, c.800 mi (1,290 km) long and from 30 to 100 mi (50–160 km) wide, SW Africa, along the coast of Namibia. It occupies a rocky platform between the Atlantic Ocean and the...