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morning glory

(Encyclopedia)CE5 Morning glory, Convolvulus arvensis morning glory, common name for members of the Convolvulaceae, a family of herbs, shrubs, and small trees (many of them climbing forms) inhabiting warm regio...

lysine

(Encyclopedia)CE5 lysine līˈsēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essential amino...

phase, in astronomy

(Encyclopedia)CE5 Phases of the moon phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most ofte...

capital, in architecture

(Encyclopedia)CE5 A. Types of capitals B. Parts of a capital capital, in architecture, the crowning member of a column, pilaster, or pier. It acts as the bearing member beneath the lintel or arch supported by t...

valerian, in botany

(Encyclopedia)CE5 Valerian, Valeriana officinalis valerian, common name for some members of the Valerianaceae, a family chiefly of herbs and shrubs of temperate and colder regions of the Northern Hemisphere; a ...

vein

(Encyclopedia)CE5 Cross section of vein showing valves vein, blood vessel that returns blood to the heart. Except for the pulmonary vein, which carries oxygenated blood from the lungs to the heart, veins carry ...

adenosine triphosphate

(Encyclopedia)CE5 Adenosine triphosphate (ATP) adenosine triphosphate (ATP) ədĕnˈəsēn trīˌfŏsˈfāt [key], organic compound composed of adenine, the sugar ribose, and three phosphate groups. ATP serves ...

wheel and axle

(Encyclopedia)CE5 Wheel and axle wheel and axle, simple machine consisting of a wheel mounted rigidly upon an axle or drum of smaller diameter, the wheel and the axle having the same axis. It is fundamentally a...

triumphal arch

(Encyclopedia)CE5 Triumphal arch triumphal arch, monumental structure embodying one or more arched passages, frequently built to span a road and designed to honor a king or general or to commemorate a military ...

tryptophan

(Encyclopedia)CE5 tryptophan trĭpˈtəfăn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essent...