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toxin

(Encyclopedia)toxin, poison produced by living organisms. Toxins are classified as either exotoxins or endotoxins. Exotoxins are a diverse group of soluble proteins released into the surrounding tissue by living ba...

senility

(Encyclopedia)senility sənilˈətē [key], deterioration of body and mind associated with old age. Indications of old age vary in the time of their appearance. Stooped posture, wrinkled skin, decrease in muscle st...

plant breeding

(Encyclopedia)plant breeding, science of altering the genetic pattern of plants in order to increase their value. Increased crop yield is the primary aim of most plant-breeding programs; advantages of the hybrids a...

Cayenne

(Encyclopedia)Cayenne kīĕnˈ, kāĕnˈ [key], city and district (2021 est. pop. 61,550), capital of French Guiana, on Cayenne isl...

Raglan, Fitzroy James Henry Somerset, 1st Baron

(Encyclopedia)Raglan, Fitzroy James Henry Somerset, 1st Baron, 1788–1855, British general. He entered the army in 1804 and was made (1814) a lieutenant colonel for his services on the duke of Wellington's staff i...

Venter, Craig

(Encyclopedia)Venter, Craig (John Craig Venter), 1946–, American biotechnologist and pioneering genome mapper, b. Salt Lake City, grad. Univ. of California, San Diego (B.A. 1972, Ph.D. 1975). Joining the National...

depressant

(Encyclopedia)depressant, any one of various substances that diminish functional activity, usually by depressing the nervous system. Barbiturates, sedatives, alcohol, and meprobamate are all depressants. Depressant...

dogwood

(Encyclopedia)dogwood or cornel kôrˈnəl [key], shrub or tree of the genus Cornus, chiefly of north temperate and tropical mountain regions, characteristically having an inconspicuous flower surrounded by large, ...

DDT

(Encyclopedia)DDT or 2,2-bis(p-chlorophenyl)-1,1,1,-trichloroethane, chlorinated hydrocarbon compound used as an insecticide. First introduced during the 1940s, it killed insects that spread disease and fed on crop...

neostigmine

(Encyclopedia)neostigmine nēˌōstĭgˈmēn, –mĭn [key], drug used to mimic the effects of stimulation of the parasympathetic nervous system. Along with several other drugs that have a similar mode of action, i...