BIOL 2P97 Final: Gastrointestinal Physiology-EXAM.docx

• School: Brock University
• Department: Biological Sciences
• Course: BIOL 2P97
• Professor: Joe Smuczek

Document Summary

Gastrointestinal physiology: gastrointestinal tract, gi tract, alimentary tract, a tube passing through the body, closed off by a skeletal muscle sphincter at each end, the gi tract opens to the outside world. Therefore, it is considered part of the external environment. It must be reabsorbed very rapidly to prevent dehydration. Challenges of the gi tract: don"t get dehydrated: reabsorption is very efficient, only 100 ml of fluid is lost in the feces, conditions that lead to vomiting and diarrhea can quickly cause dehydration. Defense mechanisms: mucus, digestive enzymes, gut associated lymphoid tissue = galt, largest collection of the lymphoid tissue in the body, 80% of the body"s lymphocytes. Meeting these challenges: by coordinating the 4 basic processes of the gi tract, digestion, absorption, motility, secretion. Anatomy of the digest system: oral cavity, receptacle for food, place for physical digestion (chewing, lubrication and moistening of food through saliva, salivary glands, submandibular under the mandible, sublingual under the tongue, parotid.