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mutation

(Encyclopedia)mutation, in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any change in the delica...

anatomy

(Encyclopedia)anatomy ənătˈəmē [key], branch of biology concerned with the study of body structure of various organisms, including humans. Comparative anatomy is concerned with the structural differences of pl...

antiviral drug

(Encyclopedia)antiviral drug, any of several drugs used to treat viral infections. The drugs act by interfering with a virus's ability to enter a host cell and replicate itself with the host cell's DNA. Some drugs ...

forgery, in art

(Encyclopedia)forgery, in art, the false claim to authenticity for a work of art. A forger often unconsciously produces a confusion of styles or subtly accents elements reflecting contemporary bias. A major examp...

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...

actin

(Encyclopedia)actin, a protein abundantly present in many cells, especially muscle cells, that significantly contributes to the cell's structure and motility. Actin can very quickly assemble into long polymer rods ...

Horvitz, H. Robert

(Encyclopedia)Horvitz, H. Robert (Howard Robert Horivtz), 1947–, American geneticist, b. Chicago, Ill., Ph.D. Harvard, 1974. Horvitz has been a professor at the Massachusetts Institute of Technology since 1978. W...

cyclosis

(Encyclopedia)cyclosis sīklōˈsĭs [key], streaming of cytoplasm within a living cell without deformation of the external cell membrane. In some plant cells there is a rapid rotatory cytoplasmic movement, which i...

microbiology

(Encyclopedia)microbiology: see biology.

synapse

(Encyclopedia)synapse sĭnˈăps [key], junction between various signal-transmitter cells, either between two neurons or between a neuron and a muscle or gland. A nerve impulse reaches the synapse through the axon,...