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sap
(Encyclopedia)sap, fluid in plants consisting of water and dissolved substances. Cell sap refers to this fluid present in the large vacuole, or cell cavity, that occupies most of the central portion of mature plant...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 ...carbon
(Encyclopedia)CE5 The three solid forms of pure carbon: In the diamond crystal each carbon atom is surrounded symmetrically by four other carbons (at each of the four corners of a tetrahedron). In the graphite c...aquarium
(Encyclopedia)aquarium, name for any supervised exhibit of aquatic animals and plants. Aquariums are known to have been constructed in ancient Rome, Egypt, and Asia. Goldfish have been bred in China for several hun...photochemistry
(Encyclopedia)photochemistry, study of chemical processes that are accompanied by or catalyzed by the emission or absorption of visible light or ultraviolet radiation. A molecule in its ground (unexcited) state can...algae
(Encyclopedia)algae ălˈjē [key] [plural of Lat. alga=seaweed], a large and diverse group of primarily aquatic plantlike organisms. These organisms were previously classified as a primitive subkingdom of the plan...starch
(Encyclopedia)starch, white, odorless, tasteless, carbohydrate powder. It plays a vital role in the biochemistry of both plants and animals and has important commercial uses. In green plants starch is produced by p...carbohydrate
(Encyclopedia)carbohydrate, any member of a large class of chemical compounds that includes sugars, starches, cellulose, and related compounds. These compounds are produced naturally by green plants from carbon dio...phosphorylation
(Encyclopedia)phosphorylation, chemical process in which a phosphate group is added to an organic molecule. In living cells phosphorylation is associated with respiration, which takes place in the cell's mitochondr...cave
(Encyclopedia)cave, a cavity in the earth's surface usually large enough for a person to enter. Caves may be formed by the chemical and mechanical action of a stream upon soluble or soft rock, of rainwater seeping ...Browse by Subject
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