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tree

(Encyclopedia)CE5 Types of trees tree, perennial woody plant with a single main stem (the trunk, or bole) from which branches and twigs extend to form a characteristic crown of foliage. In general, a tree diffe...

recombination

(Encyclopedia)recombination, process of “shuffling” of genes by which new combinations can be generated. In recombination through sexual reproduction, the offspring's complete set of genes differs from that of ...

Balzac, Honoré de

(Encyclopedia)Balzac, Honoré de bălˈzăk, bôl–, Fr. ōnôrāˈ də bälzäkˈ [key], 1799–1850, French novelist, b. Tours. Balzac ranks among the great masters of the novel. Of a bourgeois family, he himsel...

personal computer

(Encyclopedia)personal computer (PC), small but powerful computer primarily used in an office or home without the need to be connected to a larger computer. PCs evolved after the development of the microprocessor m...

fern

(Encyclopedia)CE5 Life cycle of a fern fern, any plant of the division Polypodiophyta. Fern species, numbering several thousand, are found throughout the world but are especially abundant in tropical rain fores...

Porifera

(Encyclopedia)CE5 A. Canal systems of the three morphological types of sponges B. Internal anatomy of an asconoid sponge, representative of the phylum Porifera Porifera pōrĭfˈərə [key] [Lat.,=pore bearer],...

mask

(Encyclopedia)mask, cover or partial cover for the face or head used as a disguise or protection. Masks have been worn from time immemorial throughout the world. They are used by primitive peoples chiefly to impers...

Bell, Alexander Graham

(Encyclopedia)Bell, Alexander Graham, 1847–1922, American scientist, inventor of the telephone, b. Edinburgh, Scotland, educated at the Univ. of Edinburgh and University College, London; son of Alexander Melville...

clone

(Encyclopedia)clone, group of organisms, all of which are descended from a single individual through asexual reproduction, as in a pure cell culture of bacteria. Except for changes in the hereditary material that c...

moss, in botany

(Encyclopedia)CE5 Life cycle of a moss: A germinating spore forms a transitory branching structure on the soil surface, which develops into the conspicuous gametophyte, the familiar moss plant. Eggs and sperm ar...