Either of two pairs of cords or folds of mucous membrane that extend across the interior cavity of the larynx, primarily responsible for voice production. This consists of a thicker upper pair, called false vocal cords because they are not involved in voice production, and a lower pair, called true vocal cords. Voice is produced when air from the lungs causes the lower cords to vibrate. Pitch is controlled by varying the tension on the cords. Volume is controlled by regulating the air passing through the larynx. The vocal cords are shorter and thinner in women and children, accounting in part for their higher-pitched voices.