week 2: digestion and absorption Flashcards
function of the GI tract (6)
- secretion of substances to speed up digestion
- release of hormones for digestion/ metabolism
- digestion of food
- absorption
- fermentation
- excretion of waste
function of the stomach (2)
- mixes food into a liquid mass [chyme]
- secretes acid and enzymes for protein digestion and minimal lipid digestion
small intestine (2)
- primary site of digestion and absorption
- 8-10 hours to move food through
liver makes ___ and is needed for ____
liver makes bile and is needed for fat absorption
gallbladder stores ____ and releases it ____
gallbladder stores bile and releases it into the small intestine
pancreas makes ____ and releases them ____
pancreas makes digestive enzymes and releases them into the small intestine
large intestine
- most nutrients have already been absorbed
- minimal digestion
- no enzyme secretion
gastro esophageal sphincter
prevents stomach contents from coming up
pyloric sphincter
slows rate of movement of chyme from stomach to small intestine
segmentation
ring like contraction of muscles in the small intestine to break mass into smaller pieces
chemical phase of digestion (2)
- stomach acid breaks some chemical bonds
- enzymes for breaking specific bonds
gastrin
- food in stomach stimulates stomach acids
cholecystokinin (CCK)
- fat in small intestine stimulates liver secretions
secretin
- acid in small intestine stimulates bicarbonate from pancreas to neutralize acid
absorption
- movement of small molecules across the GIT wall from intestinal lumen to blood or lymph
majority of absorption occurs in ____ via _____
- majority of absorption occurs in the small intestine via ville and microville
passive vs facilitated diffusion
- passive = no protein carrier
- facilitated = needs protein carrier
active transport (uses/ does not use) energy, while diffusion (does/ does not)
- active transport uses energy while diffusion does not
ulcer is caused by ____ but is not caused by ____
- caused by H. pylori but is not caused by stress, alcohol or smoking
treatment of heartburn
- weight loss
- avoid overfilling stomach
- smaller meals
- avoid laying down after meals
- medication
gallstones
- blockage of bile duct from gallbladder
treatment of celiac disease
- need to avoid all gluten containing foods
- gluten found in wheat, rye and barley
diverticulitis can be caused by ___
- low fiber diet
