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hemoglobin

(Encyclopedia)hemoglobin hēˈməglōˌbĭn [key], respiratory protein found in the red blood cells (erythrocytes) of all vertebrates and some invertebrates. A hemoglobin molecule is composed of a protein group, kn...

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...

iridium

(Encyclopedia)iridium ĭrĭdˈēəm [key], metallic chemical element; symbol Ir; at. no. 77; at. wt. 192.217; m.p. about 2,410℃; b.p. about 4,130℃; sp. gr. 22.55 at 20℃; valence +3 or +4. Iridium is a very ha...

Jacob, François

(Encyclopedia)Jacob, François fräNswäˈ zhäkôbˈ [key], 1920–2013, French biologist and geneticist, educated at the Sorbonne. His medical studies were interrupted by World War II. He joined the Free French F...

almond

(Encyclopedia)almond, name for a small tree (Prunus amygdalus) of the family Rosaceae (rose family) and for the nutlike, edible seed of its drupe fruit. The “nuts” of sweet-almond varieties are eaten raw or roa...

cadmium

(Encyclopedia)cadmium kădˈmēəm [key] [from cadmia, Lat. for calamine, with which cadmium is found associated], metallic chemical element; symbol Cd; at. no. 48; at. wt. 112.411; m.p. 321℃; b.p. 765℃; sp. gr...

Watson, James Dewey

(Encyclopedia)Watson, James Dewey, 1928–, American biologist and educator, b. Chicago, Ill., grad. Univ. of Chicago, 1947, Ph.D. Univ. of Indiana, 1950. With F. H. C. Crick he began (1951) research on the molecul...

bog

(Encyclopedia)bog, very old lake without inlet or outlet that becomes acid and is gradually overgrown with a characteristic vegetation (see swamp). Peat moss, or sphagnum, grows around the edge of the open water of...

Bolshoi Ballet

(Encyclopedia)Bolshoi Ballet bōlˈshoi, bôlˈ– [key], one of the principal ballet companies of Russia; part of the Bolshoi Theatre, which also includes Russia's premier opera company. The Bolshoi Ballet began a...

fats and oils

(Encyclopedia)fats and oils, group of organic substances that form an important part of the diet and also are useful in many industries. The fats are usually solid, the oils generally liquid at ordinary room temper...