Human digestive systems Flashcards
what happens in the mouth in human digestive system
mechanical digestion: teeth chews food to smaller pieces that are easier to extract nutrients from
chemical digestion: food mixed with saliva that has digestive enzymes that further break down food
what is bolus?
partially digested ball of food
what is peristalsis?
rhythmic contractions that push food through the digestive pathway
what happens in the stomach in the human digestive system?
mechanical digestion: stomach churns– further mixes and breaks down food
chemical digestion: stomach acids are mixed in with food– continues breaking down food into smaller pieces makes substance called chyme that is gradually released into the small intestine
what is chyme?
food broken down and mixed with acidic liquid
where does the most chemical digestion occur?
small intestine
what happens in the duodenum?
chyme mixed with bile from liver and pancreatic juices from pancreas to neutralise it and continue breaking it down further
what are the 3 parts of the small intestine?
duodenum, jejunum, ileum
what happens in the ileum?
nutrients are absorbed through villi into bloodstream
what are villi?
finger like projections that are one cell thick and have an extremely high surface area to volume ratio for increasing absorption
what does the large intestine do?
absorbs water+ vitamins+minerals
what happens in the colon/rectum?
remaining matter is stored as faeces and excreted during bowel movements
basic summary of human digestive tract?
mouth– oesophagus– stomach– small intestine- large intestine- colon/rectum– anus
