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eukaryote

(Encyclopedia)eukaryote yo͞okârˈē-ōtˌ [key], a cell or organism composed of cells that have a membrane-bound nucleus and organelles (mitochondria, chloroplasts; see cell, in biology) and genetic material orga...

killer whale

(Encyclopedia)killer whale, orca, or grampus, a large, rapacious marine mammal of the dolphin family. Historically considered one species, Orcinus orca, killer whales may be classified into several types, based on...

skin

(Encyclopedia)CE5 Cross section of skin skin, the flexible tissue (integument) enclosing the body of vertebrate animals. In humans and other mammals, the skin operates a complex organ of numerous structures (so...

micromechanics

(Encyclopedia)micromechanics, the combination of minuscule electrical and mechanical components in a single device less than 1 mm across, such as a valve or a motor. Although micromechanical production processes an...

giraffe

(Encyclopedia)giraffe, African ruminant mammal, genus Giraffa, living in open savanna S of the Sahara. Giraffes have historically been considered to be one species, G. camelopardalis, with a number of subspecies, b...

Darwin's finches

(Encyclopedia)Darwin's finches or Galapagos finches gəläˈpəgōsˌ [key], species of small perching birds, constituting the subfamily Geospizinae of the tanager family. Not related to the true finches, this grou...

antioxidant

(Encyclopedia)antioxidant, substance that prevents or slows the breakdown of another substance by oxygen. Synthetic and natural antioxidants are used to slow the deterioration of gasoline and rubber, and such antio...

interferon

(Encyclopedia)interferon ĭnˌtərfērˈŏn [key], any of a group of proteins produced by cells in the body in response to an attack by a virus. A cell infected by a virus releases minute amounts of interferons, wh...

pharming

(Encyclopedia)pharming färˈmĭng [key], the use of genetically altered livestock, such as cows, goats, pigs, and chickens, to produce medically useful products. In pharming, researchers first create hybrid genes ...

virus

(Encyclopedia)CE5 Structure of a tobacco mosaic virus, an RNA-containing virus virus, parasite with a noncellular structure composed mainly of nucleic acid within a protein coat. Most viruses are too small (100...