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nucleic acid

(Encyclopedia)CE5 Replication of strands of DNA CE5 nucleic acid, any of a group of organic substances found in the chromosomes of living cells and viruses that play a central role in the storage and replica...

genetics

(Encyclopedia)genetics, scientific study of the mechanism of heredity. While Gregor Mendel first presented his findings on the statistical laws governing the transmission of certain traits from generation to genera...

Obama, Barack

(Encyclopedia)Obama, Barack (Barack Hussein Obama 2d), bəräkˈ ho͞osānˈ ōbäˈmə [key], 1961–, 44th president of the United States (2009–17), b. Honolulu, grad. Columbia (B.A. 1983), Harvard Law School ...

mathematics

(Encyclopedia)mathematics, deductive study of numbers, geometry, and various abstract constructs, or structures; the latter often “abstract” the features common to several models derived from the empirical, or ...

African languages

(Encyclopedia)African languages, geographic rather than linguistic classification of languages spoken on the African continent. Historically the term refers to the languages of sub-Saharan Africa, which do not belo...

Chordata

(Encyclopedia)CE5 Common features in representative groups of the phylum Chordata Chordata kôrdāˈtə, –däˈ– [key], phylum of animals having a notochord, or dorsal stiffening rod, as the chief internal ...

Alabama, state, United States

(Encyclopedia)CE5 Alabama ăləbămˈə [key], state in the SE United States. It is bordered by Tennessee (N), Georgia (E), Florida and the Gulf of Mexico (S), and Mississippi (W). In 1954 the U.S. Supreme Co...

Benin, country, Africa

(Encyclopedia)CE5 Benin bĕnēnˈ [key], officially Republic of Benin, republic (2020 est. pop. 12,120,000), ...

air pollution

(Encyclopedia)air pollution, contamination of the air by noxious gases and minute particles of solid and liquid matter (particulates) in concentrations that endanger health. The major sources of air pollution are t...

volcano

(Encyclopedia)volcano, vents or fissures in the earth's crust through which gases, molten rock, or lava, and solid fragments are discharged. Their study is called volcanology. The term volcano is commonly applied b...