Vocal cords. Bronchoscope image showing the human vocal cords at rest - the cords appear separated. The vocal cords move in relationship to each other to interfere with the airflow out of the larynx, and thus produce the audible vibrations that constitute speech. In the upper frame is the epiglottis, a leaf-shaped flap which covers the entrance to the larynx when food is being swallowed. The bronchoscope is a type of endoscope, a flexible cable carrying a light source which allows observation of otherwise inaccessible areas of the body.