How Do We Speak?
Only man has the power to express himself among all the living beings. Different types of sounds can be produced by them.
Do you know how do we speak?
There is a hollow organ in our throat which is known as ‘Larynx’ or ‘sound box’. Actually, it is an enlarge part of the wind pipe. The walls of the larynx are made up of cartilage and these walls are lined from inside with mucus membrane. The cartilage is made up of soft bony substance. This material is 
also used to make the outer part of our ears. On the two sides of the sound box, there are two vocal chords. Sixteen muscles control their movements. The vocal chords start vibrating when the air from the lungs passes through them. Due to these vibrations sound is produced. The sweetness, hoarseness and sharpness of sound depend upon the pressure of the vocal chords. The muscles control the pressure of the vocal chords. Under higher pressure the vocal chords can vibrate up to 1000 times per second and produce melodious sounds. Actually, more number of vibrations produces sharper sound, whereas less number of vibrations produces heavier sound. The rate of the vibrations changes from person to person. Therefore the quality of sound is also different in different people. The vocal chords of a child become thicker at the age of 13-14 years. Due to which their frequency of vibrations is reduced. Then the pitch of the voice gets lower. Not only the vocal chords, our stomach, lips, tongue, chests, teeth are also concerned in the production of sound.
