Palatopharyngeus muscle
Encyclopedia
The palatopharyngeus or palatopharyngeal or pharyngopalatinus muscle is a long, fleshy fasciculus, narrower in the middle than at either end, forming, with the mucous membrane covering its surface, the palatopharyngeal arch
Palatopharyngeal arch
The palatopharyngeal arch is larger and projects farther toward the middle line than the anterior; it runs downward, lateralward, and backward to the side of the pharynx, and is formed by the projection of the Pharyngopalatinus, covered by mucous membrane....

.

Origin and insertion

It is separated from the palatoglossus muscle
Palatoglossus muscle
The palatoglossus, glossopalatinus, or palatoglossal muscle is a small fleshy fasciculus, narrower in the middle than at either end, forming, with the mucous membrane covering its surface, the glossopalatine arch....

 by an angular interval, in which the palatine tonsil is lodged. It arises from the soft palate, where it is divided into two fasciculi by the levator veli palatini
Levator veli palatini
The levator veli palatini is the elevator muscle of the soft palate in the human body. During swallowing, it contracts, elevating the soft palate to help prevent food from entering the nasopharynx...

 and musculus uvulae
Musculus uvulae
The musculus uvulae is a muscle of the soft palate.-Origin and insertion:It arises from the posterior nasal spine of the palatine bones and from the palatine aponeurosis....

.
  • The posterior fasciculus lies in contact with the mucous membrane
    Mucous membrane
    The mucous membranes are linings of mostly endodermal origin, covered in epithelium, which are involved in absorption and secretion. They line cavities that are exposed to the external environment and internal organs...

    , and joins with that of the opposite muscle in the middle line.
  • The anterior fasciculus, the thicker, lies in the soft palate
    Soft palate
    The soft palate is the soft tissue constituting the back of the roof of the mouth. The soft palate is distinguished from the hard palate at the front of the mouth in that it does not contain bone....

     between the levator
    Levator veli palatini
    The levator veli palatini is the elevator muscle of the soft palate in the human body. During swallowing, it contracts, elevating the soft palate to help prevent food from entering the nasopharynx...

     and tensor
    Tensor veli palatini muscle
    The tensor veli palatini is a broad, thin, ribbon-like muscle in the head that tenses the soft palate.-Structure:The tensor veli palatini is found anterior-lateral to the levator veli palatini muscle....

     veli palatini muscles, and joins in the middle line the corresponding part of the opposite muscle.


Passing lateralward and downward behind the palatine tonsil, the palatopharyngeus joins the stylopharyngeus and is inserted with that muscle into the posterior border of the thyroid cartilage, some of its fibers being lost on the side of the pharynx
Pharynx
The human pharynx is the part of the throat situated immediately posterior to the mouth and nasal cavity, and anterior to the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx , the oropharynx , and the laryngopharynx...

 and others passing across the middle line posteriorly to decussate with the muscle of the opposite side.

Action

The palatine velum is slightly raised by the levator veli palatini
Levator veli palatini
The levator veli palatini is the elevator muscle of the soft palate in the human body. During swallowing, it contracts, elevating the soft palate to help prevent food from entering the nasopharynx...

 and made tense by the tensor veli palatini; the palatopharyngeus muscles, by their contraction, pull the pharynx
Pharynx
The human pharynx is the part of the throat situated immediately posterior to the mouth and nasal cavity, and anterior to the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx , the oropharynx , and the laryngopharynx...

 upward over the bolus
Bolus (digestion)
In digestion, a bolus is a mass of food that has been chewed at the point of swallowing. Once a bolus reaches the stomach, digestion begins....

 of food and nearly come together, the uvula filling up the slight interval between them.

By these means the bolus is prevented from passing into the nasopharynx
Nasopharynx
The nasopharynx is the uppermost part of the pharynx. It extends from the base of the skull to the upper surface of the soft palate; it differs from the oral and laryngeal parts of the pharynx in that its cavity always remains patent .-Lateral:On its lateral wall is the pharyngeal ostium of the...

; at the same time, the palatopharyngeus muscles form an inclined plane, directed obliquely downward and backward, along the under surface of which the bolus descends into the lower part of the pharynx.
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