digestive system Flashcards
what is the function of the digestive system
chemical and physical process of breaking down large food molecules into smaller nutrients that can be absorbed by the body
what are the 4 stages of digestion
- INGESTION: eating food
- DIGESTION: breakdown of food by mechanical or chemical processes to be absorbed
- ABSORPTION: transport of products of digestion from digestive system into circulatory system
- ELIMINATION: removal of undigested solid waste matter from body
what is the difference between physical and chemical digestion
PHYSICAL: breaking apart large particles down to smaller units
- mechanical process: teeth, tongue, churning
CHEMICAL: chemical breakdown of nutrient molecules into small molecules by enzymes
role of liver
- secretes bile
- breaks large fat droplets into smaller ones
role of gall bladder
stores and concentrates bile
role of pancreas
- regulates blood sugar- produces hormones
- produces pancreatic juices- enzymes & bicarbonate
explain the path food takes through the digestive system
the GI tract takes food from mouth through esophagus, stomach, small + large intestine, rectum, anus
- nutrients and water absorbed from body
- what is leftover is moved by GI tract until it is removed from the body through the rectum/anus
trypsin
- released from pancreas
- break down long chains into shorter peptides
erepsin
- released from pancreas + small intestine
- break protein bonds in short peptides into amino acids
amylase
- released by pancreas
- continues digestion that began in mouth
- carbohydrates break down into disaccharides
disaccharides (maltase, lactase, sucrase)
- released by small intestine
- complete carbohydrate digestion
pepsinogen
- inactive precursor to pepsin
- HCl converts it to pepsin
pepsin
breaks down proteins into shorter chains
lipase
breaks down into glycerol and fatty acids
functions in small intestine
cholecystokinin (CCK)
- fats enter duodenum stimulate release of CCK
- bloodstream carries CCK to gall bladder
