BACK TO ALIMENTARY - ANATOMY & PHYSIOLOGY

Introduction

The pharynx is a chamber connecting the oral cavity, nasal cavity, oesophagus and larynx. The pharynx is divided into the nasal pharynx, oral pharynx and oesophageal/laryngeal pharynx which all have different functions, innervation and develope differently.

The oropharynx is the oral section of the pharynx.


Functional Anatomy

  • Last molar rostrally
  • Epiglottis caudally
  • Tongue ventrally
  • Soft palate dorsally
  • Endoderm
  • Innervated by glossopharyngeal nerve (CN IX)
  • Divided by glossopalatine arch from oesophageal pharynx


Musculature

Constrictors

  • Hyopharyngeus
  • Thyropharyngeus
  • Cricopharyngeus

Dilators

  • Stylopharyngeus

Shorten

  • Pterygopharyngeus

Close Pharyngeal Arch

  • Palatopharyngeus


Innervation

  • Muscles from pharyngeal arch 4 innervated by vagus nerve (CN X)
  • Stylopharyngeus from pharyngeal arch 3 innervated by glossopharyngeal nerve (CN IX)


Histology

  • Stratified squamous epithelium
  • Keratinised in ruminants