The structure indicated is the soft palate.
The hard and soft palates form the roof of the oral cavity. The oral cavity opens anteriorly on the face via the oral fissure. Posteriorly the oral cavity opens into the oropharynx via oropharyngeal isthmus. The floor is formed mainly of the tongue and surrounding soft tissue. Laterally, the oral cavity is bounded by the muscular cheeks.
The hard palate forms the anterior portion of the roof of the oral cavity and consists of a plate of bone (from the maxilla and palatine bones) covered in mucosa.
Posteriorly, the soft palate is continuous with the hard palate. It is called “soft” as the mucosa of which it is formed does not lie over bone, but instead is draped over muscles. There are five muscles which are involved in moving the soft palate:
- Tensor veli palatini
- Levator veli palatini
- Musculus uvulae
The soft palate is mobile and can act to seal off the nasopharynx when it is elevated, and it can be lowered to seal off the oropharyngeal isthmus.