Slide 2: The posterior aperture (choanae) of the nasal cavities open into the
The posterior opening of the oral cavity (oropharyngeal isthmus) opens into the
The superior aperture of the larynx (laryngeal inlet) opens into the laryngopharynx.
Slide 5: According to the anterior relationship the pharynx is sundivided into three
Slide 10: Enlarge of this tonsil,known as adnoids, can occlude the nasppharynx so that
breathing is only possible through the oral cavity.
Slide 15: * When holding liquid or solids in the oral cavity, the oropharyngeal isthmus
is closed by depression of the soft palate, elevation of the back of the tongue, and
movement toward the midline of the palatoglossal and palatopharyngeal folds. This
allows person to breath while chewing or manipulating material in the oral cavity.
On swallowing, the oropharyngeal isthmus is opened, the palate is elevated, the
pharyngeal cavity is closed, and the food or liquid is dericed into the esophagus. A
person can not breath and swallow at the same time because the airway is closed at
two sites , the paryngeal isthmus and the larynx.
** The palatin tonsils are visible through the oral cavity just posterior to the
Slide 20: * The pyriform fossea form channels that direct solids and liquids from oral
cavity around the raised laryngeal inlet and into the esophagus.
Slide 22: show pyriform fossae and posterior view of pharyngeal wall opend
Slide 24: *The pharyngeal wall is formed by skeletal muscles and by fascia
** The muscles of the pharynx are organized into two groups based on the orientation
of muscle fibers.
1. constrictor muscles have thefibers oriented in a circular direction relative to the
2. longitudinal muscles have fibers orientedvertically.
3. levator palati, tensor palati,palato-glossus,etc control the soft palate
Slide 25: * Contracting in succession squeeze the food downwards to the esophageal
Slide 29: * which sandwich the pharyngeal muscles between them.
** The fascia reinforces the pharyngeal wall where muscle is deficient. This is
particularly evident above the level of the superior constrictor where the pharyngeal
wall is formed almost entirely of fascia.
Slide 34: * Collection of lymphoid tissue in the mucosa of the pharynx surrounding
the openings of the nasal and oral cavity are part of the body’s defence system. The
largest of these collections form the distict masses (tonsils).
Slide 46: * Motor and most sensory innervation of the pharynx is mainly through
branches of the vagus nerve[Ⅹ] and glossopharyngeal nerve[Ⅸ],which form a plexus
in the outer fascia of the pharyngeal wall.