The Larynx
The larynx, commonly called the voice box, is an organ in the neck of amphibians, reptiles, and mammals involved in breathing, sound production, and protecting the trachea against food aspiration. It manipulates pitch and volume. The larynx houses the vocal folds (vocal cords), which are essential for phonation.
The Vocal Tract
The vocal tract is the cavity in human beings and in animals where sound that is produced at the sound source (larynx in mammals; syrinx in birds) is filtered. The estimated average length of the vocal tract in adult male humans is 16.9 cm and 14.1 cm in adult females
You really need to study the above diagrams so as to understand how your everlasting musical instrument(Your Voice) works. No time wasted as it enables you know the value of it and how to maintain it for best performance.
I'll like to pause here per chance I have some readers who have not come to understand the vocal system. Fell free to ask your questions as comments and we will try our best to provide you with the best answers.