Choose three symbiotic partners—one that illustrates mutualism, one that illustrates commensalism, and one that illustrates parasitism. write a short paragraph (2-4 sentences) for each of the three symbiotic partners you chose, explaining how symbiosis functions in the partnership.

The pharynx is a passageway that is common to the respiratory and digestive system. It connects nasal and oral cavity with the trachea and esophagus Oropharynx- ventral to the soft palate Nasopharynx-dorsal to the soft palate Laryngopharynx- caudal to the soft palate Define the pharynx and its parts Hard palate dorsally Tongue ventrally Teeth laterally and rostrally What structures outline the oral cavity proper? It is the space outside the teeth/gums and inside the lip/cheek What is the vestibule The palatoglossal arch divides the oropharynx and oral cavity. It is a mucosal fold that extends between the body and root of the tongue to the beginning to the soft palate. Identify the structure outlined in red. Which two structures does it separate? Palatine tonsil It is located in the tonsillar fossa in the oropharynx, caudal to the palatoglossal arch Identify the structure outlined in red The nasopharynx is part of the respiratory channel. Bounded rostrally by the choanae and ends at the palatopharyngeal arch which is at the caudal end of the soft palate. Red structure is the palatopharyngeal arch which extends caudally on each side from the caudal border of the soft palate to the dorsolateral wall of the laryngopharynx. It contains the opening to the auditory tube. It divides the nasopharynx and laryngopharynx. What are the boundaries of the nasopharynx (outlined in blue)? What is the structure outlined in red? Laryngopharynx It is caudal to the soft palate and dorsal to the larynx. This is the part where air from the nasopharynx crosses to reach the larynx and food and water from oropharynx cross over to reach the esophagus Red dotted line signifies air flow Identify the structure highlighted in blue. Describe its purpose and boundaries. What does the red dotted line signify?