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magic, in religion and superstition

(Encyclopedia)magic, in religion and superstition, the practice of manipulating and controlling the course of nature by preternatural means. Magic is based upon the belief that the universe is populated by unseen f...

caustic

(Encyclopedia)caustic, any strongly corrosive chemical substance, especially one that attacks organic matter. A caustic alkali is a metal hydroxide, especially that of an alkali metal; caustic soda is sodium hydrox...

histone

(Encyclopedia)histone hĭsˈtōn [key], any of a class of protein molecules found in the chromosomes of eukaryotic cells. They complex with the DNA (see nucleic acid) and pack the DNA into tight masses of chromatin...

oxalic acid

(Encyclopedia)oxalic acid ĕthˌāndīōĭk [key], HO2CCO2H, a colorless, crystalline organic carboxylic acid that melts at 189℃ with sublimation. Oxalic acid and oxalate salts are poisonous. Oxalic acid is found...

catabolism

(Encyclopedia)catabolism kətăbˈəlĭzˌəm [key], subdivision of metabolism involving all degradative chemical reactions in the living cell. Large polymeric molecules such as polysaccharides, nucleic acids, and ...

acrylic

(Encyclopedia)acrylic, artificial fiber made from a special group of vinyl compounds, primarily acrylonitrile. Acrylic fibers are thermoplastic (i.e., soften when heated, reharden upon cooling), have low moisture r...

decay of organic matter

(Encyclopedia)decay of organic matter or putrefaction, process whereby heterotrophic organisms, including some bacteria, fungi, saprophytic plants, and lower animals, utilize the remains of once-living tissue as a ...

valine

(Encyclopedia)CE5 valine vălˈēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essential am...

concentration

(Encyclopedia)concentration, in chemistry, measure of the relative proportions of two or more quantities in a mixture. The concentration of a solute is very important in studying chemical reactions because it deter...

fats and oils

(Encyclopedia)fats and oils, group of organic substances that form an important part of the diet and also are useful in many industries. The fats are usually solid, the oils generally liquid at ordinary room temper...