Median cut through head and neck, act of swallowing
Illustration of a human head and neck in cross-section on a red background. The cut partly shows cranial and facial bones (white-yellowish), especially upper and lower jaw. The spine with intervertebral discs is shown (grey). The nasal and oral cavities, as well as trachea and esophagus, are red due to their mucosa. The muscles of the mouth area are suggested. Cartilage, e.g. of the larynx, is shown in blue. It is visible that the food (bole, yellowish) inside the oral cavity should end up in the esophagus, which means that during the act of swallowing, the trachea needs to be closed up by the epiglottis. If the trachea is not or not sufficiently closed, the affected person will choke on the bole.