Material entering the digestive tract will enter the oral cavity, the region of the mouth anterior to the glossopalatine arches, formed by folds of skin extending from the tongue to the soft palate. After being torn into smaller particles, the food passes over the hard palate (1) and the soft palate (2). The edge of the soft palate is indicated by the black arrow.
The region of the system posterior to the glossopalatine arches is know as the pharynx. It is the area where the digestive and respiratory systems meet. It is divided into:
(2) Oropharynx (the area ventral to the soft palate)
(3) Laryngopharynx (the back of the throat)
Nasopharynx (the area dorsal to the soft palate, the stick is inserted into the nasopharynx)
The flap-like epiglottis (4) protects the entrance to the respiratory pathway leading to the lungs by blocking the entrance when food particles are in the laryngopharynx.
Carefully examine the relationship between the structures associated with the respiratory and digestive systems.
Air enters the respiratory pathway either through the mouth or external nares. If it enters through the nares it will flow through the nasal choanae in the skull and enter the nasopharynx located dorsal to the soft palate. #1 represents air leaving the nasopharynx and flowing into the laryngopharynx (2).
From there it passes through the glottis (3) and into the larynx (4), which houses the vocal cords. The entrance to the larynx is protected from stray particles of food by the epiglottis. From the larynx it passes into the trachea (5) and eventually into the lungs.
The finger-like structure indicated by the black arrow is the palatine tonsil.