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mucopolysaccharide

(Encyclopedia)mucopolysaccharide myo͞oˌkəpŏlēsăkˈərīd [key], class of polysaccharide molecules, also known as glycosaminoglycans, composed of amino-sugars chemically linked into repeating units that give a...

technetium

(Encyclopedia)technetium tĕknēˈshēəm [key] [Gr. technetos=artificial], artificially produced radioactive chemical element; symbol Tc; at. no. 43; mass no. of most stable isotope 98; m.p. 2,200℃; b.p. 4,877�...

alkaloid

(Encyclopedia)alkaloid, any of a class of organic compounds composed of carbon, hydrogen, nitrogen, and usually oxygen that are often derived from plants. Although the name means alkalilike, some alkaloids do not e...

alkane

(Encyclopedia)CE5 Alkanes alkane ălˈkān [key], any of a group of aliphatic hydrocarbons whose molecules contain only single bonds (see chemical bond). Alkanes have the general chemical formula CnH2n+2. An al...

essential oils

(Encyclopedia)essential oils, volatile oils that occur in plants and in general give to the plants their characteristic odors, flavors, or other such properties. Essential oils are found in various parts of the pla...

proton

(Encyclopedia)proton, elementary particle having a single positive electrical charge and constituting the nucleus of the ordinary hydrogen atom. The positive charge of the nucleus of any atom is due to its protons....

stellar populations

(Encyclopedia)stellar populations, two broadly contrasting distributions of star types that are characteristic of different parts of a galaxy. Population I stars are young, recently formed stars, whereas population...

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...

sulfur

(Encyclopedia)CE5 Sulfur crystals sulfur or sulphur sŭlˈfər [key], nonmetallic chemical element; symbol S; at. no. 16; interval in which at. wt. ranges 32.059–32.076; m.p. 112.8℃ (rhombic), 119.0℃ (mon...

chemistry

(Encyclopedia)chemistry, branch of science concerned with the properties, composition, and structure of substances and the changes they undergo when they combine or react under specified conditions. Organic chemi...