The act of protecting something by surrounding it with material that reduces or prevents the transmission of sound or heat or electricity. The material for this purpose.
A class of substances (usually proteins) that are produced by specialized cells and that travel to other parts of the body, where they influence chemical reactions and regulate ...
Form of sociopolitical organization usually based on horticulture or pastoralism. Socioeconomic stratification and centralized rule are absent in tribes, and there is no means of ...
Explanation that establishes a correlation or interrelationship between social customs. When customs are functionally interrelated, if one changes, the others also change.
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