Final answer:
The vocal cords vibrate when air passes through them, producing sound. The tension of the vocal cords and airflow from the lungs control the pitch and volume of the sound. The vocal cords open for breathing and close to produce sound.
Step-by-step explanation:
The vocal cords move to produce sound and breathe through a process called phonation. When air passes through the vocal cords, they vibrate and produce sound waves. The pitch of the sound depends on the tension of the vocal cords, controlled by muscles in the larynx. The volume of the sound is determined by the airflow from the lungs. This process allows us to speak, sing, and breathe simultaneously.
The vocal cords are located in the larynx, which is part of the throat. When we breathe, the vocal cords are relaxed and open, allowing air to pass freely into the lungs. When we produce sound, the vocal cords close and vibrate as air passes through them. The vibration produces sound waves that escape through the mouth and create speech or other vocal sounds.