digestion terms Flashcards
gastrointestinal (gi) tract
30 feet (9 meters) long continuous tube and the cells lining it function for 3-5 days, then shed into the lumen
digestive process
a multistep process of breaking down foods into absorbable components using mechanical and chemical means in the gastrointestinal (GI) tract
lumen
interior of the intestinal tract
mechanical digestion
chops us food, grinding/mixing of food, and movement of food through the system
chemical digestion
breakdown of food into absorbable nutrients
peristalsis
coordinated contractions of circular and longitudinal muscles propelling food (bolus) forward from the esophagus through the large intestine
bolus
food that has been chewed and mixed in the mouth with saliva (food mass)
segmentation
contraction of circular smooth muscle causing a sloshing motion
pendular movement
a constructive wave that involves both forward and reverse movements of chyme enhances nutrient absorption in small intestine
chyme
a semiliquid substance containing digestive secretions with the original food
gut microbiome
trillions of microbes, such as bacteria, that live in the human gut
probiotics
contain live organisms and contribute to gut health by adding specific strains of bacteria directly to the population of healthy microbes in the gut
prebiotics
plant fibers acting like fertilizers that stimulate the growth of healthy bacteria in the gut
saliva
products of mastication are mixed with saliva which contains water, electrolytes, mucus, and enzymes
mucus
lubrication and protects stomach lining from damage