Larry Neber, age 8, of La Jolla, Calif,, for his question;
What makes people able to talk?
Feel around the front of your throat gently with your fingers, You will find a roundish lump. Now speak a few words and sing some high notes and low notes. You can feel the round bump move up and down. This is your voice box where most of your speaking and singing is made. The proper name for it is the larynx.
The neck is a very important part of the body. It holds some large blood vessels, a pipe; that carries your food to the stomach and a pipe that carries the air to and from your lungs. Most of these; parts work together when you speak or sing. In the back of the neck is the top of the backbone and the body nerves which lead to the brain. But these, are sealed off from the parts in front which help make the voice.
The food pipe and the air pipe both end inside your throat. Ills you knowyou cannot use them both at once. There are muscles which close off the air pipe when you swallow, Otherwise the food gets stuck in the wrong place.
Speaking is done with the air pipe and the voice box. It is done as you breathe. The nose and mouth play a part in breathing so they also play a part in speaking. Now speak a few more words and notice: how your voice ties in with your breathing. Do you speak when you breathe my when you breathe out or when you hold your breath? Your voice will work only while you are breathing out. In fact$ you have to stop talking when you run out of breath.
The larynx and the other solid parts that make the voice are worked by the air as you. breathe it out from the lungs, The voice box is made of bands of strong gristle. Stretching across inside it from back to front are two tough strings called the vocal cords. There are muscles to move the vocal cords and make them act like violin strings.
The string on a musical instrument makes noise because a stroke, or a twang sets it vibrating, or throbbing, The vocal cords work in the same way. The rush of air as you breath out sets them twanging. Delicate muscles know how to move the vocal cords so they can make high sounds, low sounds and in between sounds.
For high sounds, the vocal cords are held tight across tile voice box. For low sounds they are held less tight. When you are not breathing, the vocal cords are relaxed. They are held apart so that the air passes easily between them as you breath.
The voice begins down in the voice box. But the speaking and singing male down there is not nearly loud or clear enough for everyday use. To make itself heard, the voice uses a megaphone. And naturally you have this under lying system built right into your head.
Sound is enlarged when it flows into caves and cavities, What it does is to bounce off the walls and double itself with echoes. The caves and cavities which enlarge your voice are in your mouth. Here also are muscles which move the sound around and alter it. The tongue itself is a strong muscle.
As you talk, notice how the tongue moves against the soft back and the hard front of the roof of your mouth to form different words. The jaws also open and close and certain sounds are made with the lips. Countless complex little muscles work together to speak a single sentence. We decide what to say and the details are carried out by our wonderful bodies without further instructions,