digestion

digestion

1. Stomach

   • parietal cells
     • denatures proteins
     • activates enzymes
     • produces HCL
   • chief cells
     • produce pepsin
     • produce rennin(chymosin)
     • gastric lipase
   • inactive enzymes for protection of stomach
     • Mucin- protective coating secreted by cell lining
     • HCL- diluted by saliva/digesta
     • urease- breaks fown urea(acts as buffer)

2. Liver

   • makes bile
   • emsulsifies soluble fats
   • forms micelles that aid in abs of fats

3. Duodenum

   • brush border produces duodenum juice(alk)
     • neutralizes chyme in stomach
     • contains weak digestive enzyme

4. Jejunum

   • primary abs. site

5. Pancreatic Juice

   • produces proteases
     • trypsin, chymotrypsin. carboxypeptidase, aminopeptidease
   • produces lipase, amylase
   • produces Buffers
     • HCO3, NACO3

6. Ascending Colon

   • not sterile (fungi,bacteria, protozoa
   • digestion is limited by
     • microbes
     • VFA
     • water abs.
     • electrolyte abs.