Pharynx

The pharynx, which has a musculomembranous structure, is an organ belonging to both respiratory and digestive systems. It is divided into three regions considering the oral cavity, nasal cavity and larynx that it neighbors. These are nasopharynx, oropharynx and laryngopharynx.
Nasopharynx; this section forms the anterior and upper part of the pharynx. The pharynx opens into the nasal cavity with choanae. Its anterior lower part is connected to the pars oralis pharyngis by the isthmus pharyngis.
In addition to functioning as part of the respiratory system, the nasopharynx is also associated with structures involved in hearing. This part of the pharynx is connected to the middle ear by a hole called the Pharyngeal opening of auditory tube. This hole is where the Eustachian tube opens into the pharynx.
Orapharynx opens to the oral cavity with the isthmus faucium on the anterior side. On the posterior side, it is a short section neighboring the 2nd and 3rd cervical vertebrae.
The laryngopharynx is located behind the larynx and terminates between the lower half of the third cervical vertebra above and the sixth cervical vertebra below. It is connected to the larynx via the aditus laryngis.
The pharynx is a special organ that also provides the delivery of food to the esophagus through the muscles in its structure.