OCB04-2009 Pharynx and Larynx Flashcards
What is the pharynx?
The upper portion of the alimentary canal
Where does the pharynx extend from and to?
From the cranial base to the lower border of the cricoid cartilage where it becomes continuous with the oesophagus
Where is the nasopharynx?
The area above the soft palate and behind the nares
What is the nasopharynx lined with?
Respiratory epithelium with goblet cells and cilia
What is the floor of the nasopharynx formed by?
The soft palate
What is the major part of the posterior wall of the nasopharynx formed by?
Superior constrictor muscles
What is the lateral wall of the nasopharynx formed by?
The opening of the pharyngotympanic tube and lymphoid tissue
What is the roof of the nasopharynx formed by?
More lymphoid tissue, the adenoid or pharyngeal tonsil
What is the oropharynx?
Area inferior to the soft palate
How is the oropharynx separated from the nasopharynx?
Raising of the soft palate
What is the anterior border of the oropharynx?
the palatoglossal and palatopharyngeal arches with the palatine tonsil sitting in between the arches
Why is the oropharynx not lined with respiratory epithelium?
It receives both air and foods so needs to have a more protective function against abrasive foods
What is the oropharynx lined with?
Stratified epithelium
What are the 4 layers of the wall of the pharynx has in common with the rest of the digestive system?
Mucosa
Submucosa
Muscular
Buccopharyngeal fascia
What is the purpose of the submucosa in the pharynx?
It contain a tough fibrous coat that anchors the pharynx to the base of the skull
What does the muscular layer of the pharynx consist of?
5 pairs of muscles forming an outer semi-circular layer, the constrictors and 2 inner longitudnal muscles
What happens to the constrictor muscles during swallowing?
Constrictor muscles contract sequentially as peristaltic waves
What is the nerve supply to the constrictor muscles?
Mostly through the pharyngeal branch of the vagus nerve
The inferior constrictor is also supplied by the recurrent branch of the vagus
What are the superior constrictor muscles?
Form a raphe between the mandible and pterygoid plate to the pharyngeal tubercle of the occipital bone
Where are the middle constrictor muscles?
From the stylohyoid ligament and horns of the hyoid to the pharyngeal raphe
Where are the inferior constrictor muscles?
From the oblique line of the hyoid and cricoid to the junction between the pharynx and oesophagus
What are the longitudinal muscles?
Palatopharyngeus muscles
Stylopharyngeus muscles
Where do the palatophayngeus muscles arise?
From the palatal aponeurosis