Columbia Encyclopedia

Search results

458 results found

albumin

(Encyclopedia)albumin ălbyo͞oˈmən [key] [Lat.,=white of egg], member of a class of water-soluble, heat-coagulating proteins. Albumins are widely distributed in plant and animal tissues, e.g., ovalbumin of egg, ...

alanine

(Encyclopedia)CE5 alanine ălˈənēnˌ [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer participates in the biosynthesis of proteins (see stereochemi...

fonio

(Encyclopedia)fonio, annual plant, genus Digitaria, of the grass family (Poaceoe). Native to Senegal, it is a type of millet grown as a staple grain throughout the Sahel region of West Africa, where it has been cul...

methotrexate

(Encyclopedia)methotrexate, drug used in halting the growth of actively proliferating tissues. Introduced in the 1950s, it is used in the treatment of leukemia, psoriasis, and non-Hodgkin's lymphoma. By binding to ...

autotroph

(Encyclopedia)autotroph ôtˈətrōfˌ [key], in biology, an organism capable of synthesizing its own organic substances from inorganic compounds. Autotrophs produce their own sugars, lipids, and amino acids using ...

arginine

(Encyclopedia)CE5 arginine ärˈjənĭn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer participates in the biosynthesis of proteins. Its basic side ...

borer

(Encyclopedia)borer, name applied to various animals that are injurious because of their ability to penetrate plant or animal tissues. Among insects, some borers are beetles, e.g., the flatheaded apple-tree borer, ...

pyrimidine

(Encyclopedia)CE5 Pyrimidines found in deoxyribonucleic acid (DNA) pyrimidine pīrĭmˈĭdēnˌ [key], type of organic base found in certain coenzymes and in the nucleic acids of plant and animal tissue. The th...

polyethylene

(Encyclopedia)polyethylene pŏlˌēĕthˈəlēn [key], widely used plastic. It is a polymer of ethylene, CH2=CH2, having the formula (–CH2–CH2–)n, and is produced at high pressures and temperatures in the pre...

Cohen, William Sebastian

(Encyclopedia)Cohen, William Sebastian, 1940–, American politician, b. Bangor, Maine. He attended Bowdoin College (B.A., 1962) and Boston Univ. (LL.B., 1965). A Republican, he was elected to the House of Represen...