the digestive system Flashcards
digestive system is responsible for
ingestion
digestion
absorption
egestion
the mouth provides mechanical:
digestion
food is physically broken down
three major nutrients that must be broken down into smaller molecules before the body can use them
carbohydrates, fats, proteins
chemical digestion uses chemicals such as
enzymes and digestive juices
the salivary glands produce
saliva
saliva contains
water, mucin, salivary amylase
water does what for the digestive system
moistens the food by dissolving it
mucin does what in the digestive system
lubricates the food for passage through the tract
what does the salivary amylase do for the digestive system
it’s an enzyme that begins the breakdown of starch into maltose
the esophagus is a muscular tube connecting your mouth to
your stomach
how does the esophagus work
smooth muscle tissue contracting and relaxing, moving partially digested food along
peristalsis: rhythmic, involuntary contraction of smooth muscle throughout
the digestive tract (esophagus)
is peristalsis voluntary or involuntary
involuntary
the stomachs lining has cells that produce
digestive juices and enzymes
contracting and relaxing stomach muscles, aka churning, is a form of
mechanical digestion
the epithelial cells from the stomach secrete
hydrochloride acid, which converts pepsinogen into pepsin
pepsinogen (stomach):
inactive enzyme
pepsin (stomach) starts
protein digestion
stomach: HCl kills bacteria to keep acid levels
high in the stomach
(stomach) chyme: liquidlike paste entering
small intestine
small intestines: kinda digested food leaves stomach, enters
first part of intestine: duodenum to be digested mechanically and chemically
small intestines: liver secretes bile, which breaks up
fat into small droplets
small intestines: pancreas secretes enzymes which break down
carbohydrates, fats, proteins
small intestines accessory organs
liver and pancreas
several enzymes decrease into small intestines to complete
chemical digestion (amylase, protease, lipase)
(small intestine) amylase: breaks down carbohydrates into
glucose
small intestines: protease breaks down proteins into
amino acids
small intestines: lipase breaks down fats into
fatty acids
the absorption of vitamins, minerals and small molecules of fats, carbohydrates, proteins into bloodstream take place
in the 2nd and 3rd portions of the small intestine
small intestines: villi are millions of inner folds that maximize surface area where
nutrients and water can be absorbed into bloodstream
inner folds inside small intestine:
villi
large intestine: where
indigestes food goes
water and electrolytes are absorbed in the
large intestine
large intestine: the rectum is at the
end, holds waste products of digestion until they go thru anus
what is ingestion
taking in food
what is absorption
diffusion of nutrients
what is digestion
breaking food down
what is egestion
removing remaining food
first section of the small intestine
duodenum
