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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...

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,...

microbiology

(Encyclopedia)microbiology: see biology.

Rodbell, Martin

(Encyclopedia)Rodbell, Martin, 1925–1998, American biochemist, b. Baltimore, Ph.D. Univ. of Washington, 1954. He was a researcher (1956–1985) at the National Heart Institute in Bethesda, Md., before becoming sc...

monoclonal antibody

(Encyclopedia)monoclonal antibody, an antibody that is mass produced in the laboratory from a single clone and that recognizes only one antigen. Monoclonal antibodies are typically made by fusing a normally short-l...

battery, electric

(Encyclopedia)CE5 Lead storage cell: At the lead-dioxide electrode, electrons from the circuit combine with lead dioxide and sulfuric acid to form lead sulfate and water. At the spongy-lead electrode, lead react...

protozoan

(Encyclopedia)protozoan prōˌtəzōˈən [key], informal term for the unicellular heterotrophs of the kingdom Protista. Protozoans comprise a large, diverse assortment of microscopic or near-microscopic organisms ...