Major Structures & Features of the Alimentary Canal (AC)

Major Structures & Features of the Alimentary Canal...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
(I° functions ) Area or accessory organ† Function of specific structures or organs Histology of structure‡ Oral Cavity Ingestion Digestion Propulstion Teeth Mastication – teeth; Chemical digestion – glands secrete saliva; aiding breakdown of starches; Mechanical digestion – tongue mixes foods; Propulsion – saliva moistens bolus; tongue moves bolus. Stratified squamous epithelium (SSE; gums, tongue, hard palate keratinized); some of 4 basic layers absent Parotid gland Sublingual g. Submandibular g. Tongue Oropharynx Propulsion Uvula Uvula prevents movement into nasopharynyx. SSE; muscularis externis layer skeletal muscle Esophagus Propulsion Gastroesophageal sphincter GS – prevents reflux of food / chyme into esophagus. Non-keratinized SSE, at GE sphincter SSE changes to simple columnar epithelium; muscularis externa- skeletal muscle upper 1/3, skeletal & smooth middle 1/3, smooth lower 1/3; adventitia vs. serosa.
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.
Ask a homework question - tutors are online