- secretion of mucus from gastric glands
- mucus protects the lining of the stomach from the acidic contents of the stomach lumen
describe the structural adaptations of the small intestine that help increase the rate at which the products of digestion can be absorbed
- plicae = folds in the walls of the digestive tract
- villi = folds in the epithelium
- microvilli = folds in the cell membrane of intestinal cells
- ALL INCREASE SURFACE AREA
hepatic portal vein, hepatic artery, bile duct
describe several functions of the liver & its anatomical connection to the alimentary canal (GI tract)
- production of bile
- storage of fat (triglycerides)
- storage of carbs (glycogen)
- conjugation of toxins to water-soluble molecules
- bile stored in gallbladder & delivered to small intestine for emulsification of fat
describe the sources of digestive enzymes along the alimentary canal
which tube in the protein digestion exp. had the most complete digestion & why?
tube with protein + pepsin + HCl @ 37 deg. celsius b/c correct enzyme was present, correct temperature, correct pH (pepsin prefers acidic pH since our stomach is acidic)
why were the other tubes in the protein digestion exp. "wrong"?
tube with pepsin = wrong pH
tube with pepsin & HCl @ 0 deg. celsius = wrong temperature
tube with HCl & water = no enzyme present
tube with pepsin & NaOH = wrong pH (NaOH too basic)
appearance of each tube in the protein digestion exp (in terms of digestion)?
tube with protein & pepsin = slightly less
tube with protein + pepsin + HCl @ 37 deg. celsius = a LOT less
tube with protein + pepsin + HCl @ 0 deg. celsius = same
tube with protein + HCl = same
tube with protein + pepsin + NaOH = same-ish
~ cream + ... ?
tube: bile salts
tube: pancreatic lipase
tube: bile salts + pancreatic lipase
tube: distilled water
which tube in the fat digestion exp. had the most complete digestion & why?
tube with bile salts & pancreatic lipase b/c bile salts act as emulsifier & enzyme is present
why were the other tubes in the fat digestion exp. "wrong"?
tube with bile salts = no enzyme present
tube with pancreatic lipase = enzyme present ; no emulsifier present
tube with distilled water = nothing in here
pH changes in the fat digestion exp?
cream + bile salts = no change
cream + pancreatic lipase = decrease pH
cream + bile salts + pancreatic lipase = LARGE pH change
cream + distilled water = no change