PHARYNX AND ESOPHAGUS

• 3 Parts of the Pharynx:

  • Nasopharynx
  • Oropharynx
  • Laryngopharynx
• Esophagus - extends between the pharynx and the stomach; 25 cm long
• 4 Tunics that make up the esophagus:

  • Mucosa
  • Submucosa
  • Muscularis
  • Adventitia
• 3 phases of swallowing (deglutition):

  • Voluntary phase - a bolus is formed and is forced toward the posterior part of the mouth and into the oropharynx
  • Pharyngeal phase (1-2 secs) - soft palate is elevated to close the nasopharynx to prevent food from entering the respiratory tract
  • Esophageal phase (5-8 secs) - food moves from pharynx to stomach