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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...

anthropology

(Encyclopedia)anthropology, classification and analysis of humans and their society, descriptively, culturally, historically, and physically. Its unique contribution to studying the bonds of human social relations ...

flower

(Encyclopedia)CE5 Longitudinal cross section of a flower at the time of fertilization, showing a pollen grain and a pollen tube. flower, name for the specialized part of a plant containing the reproductive orga...

Nabokov, Vladimir

(Encyclopedia)Nabokov, Vladimir vlädēˈmĭr näbôˈkŏf [key], 1899–1977, Russian-American author, b. St. Petersburg, Russia. He emigrated to England after the Russian Revolution of 1917 and graduated from Cam...

marsupial

(Encyclopedia)marsupial märso͞oˈpēəl [key], member of the order Marsupialia, or pouched mammals. With the exception of the New World opossums and an obscure S American family (Caenolestidae), marsupials are no...

Cenozoic era

(Encyclopedia)Cenozoic era sēnəzōˈĭk, sĕn– [key], last major division of geologic time (see Geologic Timescale, tablegeologic timescale, table) lasting from 65 million years ago to the present. The Cenozoic...

adaptation

(Encyclopedia)adaptation, in biology, has several meanings. It can mean the adjustment of living matter to environmental conditions and to other living things either in an organism's lifetime (physiological adaptat...

sheep

(Encyclopedia)sheep, common name for many species of wild and domesticated ruminant mammals of the genus Ovis of the Bovidae, or cattle, family. The male is called a ram (if castrated it is a wether), the female is...

stellar structure

(Encyclopedia)stellar structure, physical properties of a star and the processes taking place within it. Except for that of the sun, astronomers must draw their conclusions regarding stellar structure on the basis ...

dinosaur

(Encyclopedia)dinosaur dīˈnəsôr [key] [Gr., = terrible lizard], extinct land reptile of the Mesozoic era. The dinosaurs, which were egg-laying animals, ranged in length from 21⁄2 ft (91 cm) to about 127 f...