Function of Larynx is A/E

(Immunity enhancement): (303-4- Dhingra 5th edition; 577-P Hazarika 3rd)Function of the Larynx1. Primary function is to protect lower respiratory tractProtection of tracheobronchial tree is fascilitated by'Three - tier' sphincter action- Laryngeal elevation - Mylohyoid- Laryngeal tilting - Stylopharyngeous- Cricopharyngeal sphincter relaxes- Cough reflex- Cessation of respirationLarynx is aptly, called the watch-dog of lungs as it immediately barks' at the entry of any foreign intruder2. Phonation - is also an important function of the lung which facilitates communication3. Respiration: Reflex adjustments of the glottis apparatus plays a role in the mechanism of respiration Larynx regulates flow of air into the lungs.Vocal cords abduct during inspiration and adduct during expiration4. Fixation of the chest - To increase intrathoracic pressure when larynx is closed, chest wall gets fixed and various thoracic and abdominal muscles can then act best. This function is important in digging, pulling and climbing. Coughing, vomiting, defaecation, micturition and childbirth (Straining) also require a fixed thoracic cage against a closed glottis.