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Human Genome Project

(Encyclopedia)Human Genome Project, international scientific effort to map all of the genes on the 23 pairs of human chromosomes and, to sequence the 3.1 billion DNA base pairs that make up the chromosomes (see nuc...

DNA fingerprinting

(Encyclopedia)DNA fingerprinting or DNA profiling, any of several similar techniques for analyzing and comparing DNA from separate sources, used especially in law enforcement to identify suspects from hair, blood, ...

prion

(Encyclopedia)prion prēˈŏn [key], abnormal form of a protein found in mammals, now generally believed to cause a group of diseases known as prion diseases or transmissible spongiform encephalopathies, which are ...

skin cancer

(Encyclopedia)skin cancer, malignant tumor of the skin. The most common types of skin cancer are basal cell carcinoma, squamous cell carcinoma, and melanoma. Rarer forms include mycosis fungoides (a type of lymphom...

breeding

(Encyclopedia)breeding, in agriculture and animal husbandry, propagation of plants and animals by sexual reproduction; usually based on selection of parents with desirable traits to produce improved progeny. In con...

evolution

(Encyclopedia)CE5 Plant and animal evolution [Modified from Alfred Gunderson in Brooklyn Botanic Garden Leaflets, Ser. 18, No. 4 (1930); used by permission.] evolution, concept that embodies the belief that ex...

tap dance

(Encyclopedia)tap dance, theatrical dance form in which the dancer, wearing shoes with metal heel and toe taps, beats out complex, syncopated rhythms on the floor. After a slump in popularity in the 1960s, tap ...

leukemia

(Encyclopedia)leukemia lo͞okēˈmēə [key], cancerous disorder of the blood-forming tissues (bone marrow, lymphatics, liver, spleen) characterized by excessive production of immature or mature leukocytes (white b...

sex

(Encyclopedia)sex, term used to refer both to the two groups distinguished as males and females, and to the anatomical and physiological characteristics associated with maleness and femaleness. Sex relates to the t...

Neanderthal man

(Encyclopedia)Neanderthal man –tôlˌ [key], a species of Homo, the genus to which contemporary humans belong, known as H. neandertalensis after Neanderthal (now Neandertal), Germany, the valley where the first s...