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detergent

(Encyclopedia)detergent dētûrˈjənt, dĭ– [key], substance that aids in the removal of dirt. Detergents act mainly on the oily films that trap dirt particles. The detergent molecules have a hydrocarbon portion...

alkene

(Encyclopedia)CE5 Alkenes alkene ălˈkēn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon double bonds (see chemical bond). Alkenes with only one double bond h...

thymine

(Encyclopedia)thymine thīˈmēn [key], organic base of the pyrimidine family. Thymine was the first pyrimidine to be purified from a natural source, having been isolated from calf thymus and beef spleen in 1893–...

tracer

(Encyclopedia)tracer, an identifiable substance used to follow the course of a physical, chemical, or biological process. In chemistry the ideal tracer has the same chemical properties as the molecule it replaces a...

organic chemistry

(Encyclopedia)organic chemistry, branch of chemistry dealing with the compounds of carbon. While it is only the fourteenth most common element on earth, carbon forms by far the greatest number of different compound...

liposome

(Encyclopedia)liposome līˈpəsōmˌ, lĭpˈə– [key], microscopic, fluid-filled pouch whose walls are made of layers of phospholipids identical to the phospholipids that make up cell membranes. Liposomes are us...

cold, common

(Encyclopedia)cold, common, acute viral infection of the mucous membranes of the nose and throat, often involving the sinuses. The typical sore throat, sneezing, and fatigue may be accompanied by body aches, headac...

carbohydrate

(Encyclopedia)carbohydrate, any member of a large class of chemical compounds that includes sugars, starches, cellulose, and related compounds. These compounds are produced naturally by green plants from carbon dio...

coenzyme

(Encyclopedia)coenzyme kō-ĕnˈzīm [key], any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a ...

molecular biology

(Encyclopedia)molecular biology, scientific study of the molecular basis of life processes, including cellular respiration, excretion, and reproduction. The term molecular biology was coined in 1938 by Warren Weave...