which pushes air out of the lungs
Diaphragmâs Role in Breathing. When the diaphragm contracts and moves lower, the chest cavity enlarges, reducing the pressure inside the lungs. To equalize the pressure, air enters the lungs. When the diaphragm relaxes and moves back up, the elasticity of the lungs and chest wall pushes air out of the lungs. The lungs have no skeletal muscles of their own. The work of breathing is done by the diaphragm, the muscles between the ribs (intercostal muscles), the muscles in the neck, and the abdominal muscles.
Occasionally, a person may choke when food gets past the epiglottis or sticks to a structure within the pharynx and blocks the airway. The vocal folds contract to catch the blockage before it passes into the trachea. Coughing pushes air out of the lungs to force the blockage out of the airway. Sounds are produced in the larynx by the movement of air through the larynx and by the vocal folds, a pair of movable folds in the mucous membrane.