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Sound produced by humans
1. In humans, the sound is produced by the voice box or the larynx. ask students to put
fingers on the throat and find a hard bump that seems to move when we swallow.
Explain this part of the body is known as the voice box. It is at the upper end of the
windpipe. Two vocal cords, are stretched across the voice box or larynx in such a
way that it leaves a narrow slit between them for the passage of air When the lungs
force air through the slit, the vocal cords vibrate, producing sound. Muscles attached
to the vocal cords can make the cords tight or loose.
2. When the vocal cords are tight and thin, the type or quality of voice is different from
that when they are loose and thick.