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DMX

(Encyclopedia)DMX,1970-2021, b. Mount Vernon, N.Y., as Earl Simmons. DMX grew up in Yonkers, NY, in the 1980s, in a highly dysfunctional family; abandoned by his fath...

fertilization

(Encyclopedia)CE5 Fertilization of an egg cell fertilization, in biology, process in the reproduction of both plants and animals, involving the union of two unlike sex cells (gametes), the sperm and the ovum, f...

fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

ester

(Encyclopedia)CE5 Esters ester, any one of a group of organic compounds with general formula RCO2R′ (where R and R′ are alkyl groups or aryl groups) that are formed by the reaction between an alcohol and an...

behaviorism

(Encyclopedia)behaviorism, school of psychology which seeks to explain animal and human behavior entirely in terms of observable and measurable responses to environmental stimuli. Behaviorism was introduced (1913) ...

tryptophan

(Encyclopedia)CE5 tryptophan trĭpˈtəfăn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essent...

vampire bat

(Encyclopedia)vampire bat, name for the blood-drinking bats of the family Desmodontidae, found in the New World tropics. Vampire bats feed exclusively on the blood of living animals and are thus the only true paras...

Four-H

(Encyclopedia)Four-H or 4-H, organization for boys and girls, generally from 8 to 18 years of age; some states offer programs for younger children, and there are also collegiate programs. 4-H teaches young people l...

histology

(Encyclopedia)histology hĭstŏlˈəjē [key], study of the groups of specialized cells called tissues that are found in most multicellular plants and animals. Histologists study the organization of tissues at all ...

hypnotism

(Encyclopedia)hypnotism hĭpˈnətĭzəm [key] [Gr.,=putting to sleep], to induce an altered state of consciousness characterized by deep relaxation and heightened suggestibility. The term was originally coined by ...