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serine

(Encyclopedia)CE5 serine sĕrˈēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is not essential to the human die...

tyrosine

(Encyclopedia)CE5 tyrosine tīˈrəsēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is not essential to the huma...

spectral class

(Encyclopedia)CE5 spectral class, in astronomy, a classification of the stars by their spectrum and luminosity. In 1885, E. C. Pickering began the first extensive attempt to classify the stars spectroscopically....

birch

(Encyclopedia)CE5 White birch, Betula papyrifera birch, common name for some members of the Betulaceae, a family of deciduous trees or shrubs bearing male and female flowers on separate plants, widely distribut...

cephalopod

(Encyclopedia)CE5 Internal anatomy of a squid, Loligo, representative mollusk of the class Cephalopoda cephalopod sĕfˈələpŏdˌ [key], member of the class Cephalopoda, the most highly organized group of mol...

blackbody

(Encyclopedia)blackbody, in physics, an ideal black substance that absorbs all and reflects none of the radiant energy falling on it. Lampblack, or powdered carbon, which reflects less than 2% of the radiation fall...

model and modeling

(Encyclopedia)model and modeling, in painting, the use of light and shade to simulate volume in the representation of solids. In sculpture the terms denote a technique involving the use of a pliable material such a...

graph

(Encyclopedia)graph, figure that shows relationships between quantities. The graph of a function y=f (x) is the set of points with coordinates [x, f (x)] in the xy-plane, when x and y are numbers. A similar definit...

dominoes

(Encyclopedia)dominoes, game played with a set of rectangular pieces (usually 28 in number) called dominoes. Each piece (made of wood, bone, ivory, plastic, or other material) has one blank face and one face marked...

croup

(Encyclopedia)croup kro͞op [key], acute obstructive laryngitis in young children, usually between the ages of three and six. The manifestations are a high-pitched cough and difficulty in breathing, owing to a spas...