Digestive System Flashcards
what is the function of the digestive system?
-starts where? which contains? what helps breakdown the food?
-breakdown and absorption of food necessary to power the body
-starts at the mouth which contains the tongue to move food and uses the liquid saliva to assist in the breakdown of food
chewing is also known as
mastication
where does the food go after it passes the mouth?
-it travels through pharynx to the esophagus via peristalsis, contraction of muscle
what is the contraction of smooth muscle, specifically in the esophagus called?
peristalsis
after going down the esophagus, where does the food go? which can be defined as?
-the stomach which can be defined as the organ of the digestive tract found in the abdominal cavity that mixes food with powerful acidic liquid for further digestion
what is chyme? and where does it travel?
created by the stomach, it is an acidic bolus of digested food and it travels to the small intestines
what takes place in the small intestines?
-a significant amount of nutrient absorption takes place
-it contains millions of fingerlike projections called villi and microvilli
what does villi and microvilli do and where is it found?
-it increase surface area available for the absorption of nutrients found in food. it is found mostly on the ileum. absorb water-soluble digested nutrients into blood, lipids into lacteals as chylomicrons and vitamin B12
after the small intestines, where does food travel to?
-what does this organ assists in?
the large intestines
-assists in water absorption, further nutrient absorption, waste collection and production of feces
what is at the end of the large intestines?
-what are they responsible for?
rectum and anus
-which are responsible for the storage of feces and removal of feces
what are sphincters?
-muscular rings found throughout the digestive tract which regulate the movement of food through the tract and prevent reflux of material into previous cavity
where is the upper esophageal sphincter?
lower esophageal sphincter?
-between the pharynx and esophagus
-between the esophagus and stomach
where is the pyloric sphincter?
where is the ileocecal sphincter?
where is the anus?
-between the stomach and small intest.
-between the small intest. and large intest.
-between the rectum and outside the body
what are accessory organs that aid in digestion?
-salivary glands: produce salvia, breaks down the starches and fats
-liver: produces bile, which helps break down fat in the small intestines
-gallbladder: stores bile
-pancreas: produces digestive enzymes and pancreatic juice which neutralizes the acidity of chyme
what is Crohn’s disease?
an inflammatory bowel disorder that occurs when the immune system attacks the digestive system
digestive system is also known as the?
G.I tract aka gastrointestinal tract which starts with the mouth and ends in the anus
the order of the digestive tract?
mouth to pharynx (back of your throat), esophagus, stomach, small intestines, larger intestines, rectum
what are the enzymes that help breakdown starches and lipids?
-amylase and lipase
-normally released from the acinar cells of the exocrine pancreas into the duodenum
what does the gastric acid in the stomach do?
-kills bacteria , denatures proteins and activates digestive enzymes
the small intestine is broken down into:
-duodenum, jejunum, ilium ( DJ Ice)
the large intestines is broken down into:
-cecum, colon, rectum ( Come Cats Return)
what is gastrin?
-produced in stomach and stimulates stomach acid
what is cholecystokinin (CCK)?
produced in small intestines and stimulates release of enzymes form pancreas and bile from liver
what is secretin?
produced in small intestines and stimulates production of bicarbonate by pancreas
released into bloodstream by duodenum
insulin?
-produced in pancreas and regulates blood sugar levels
glucagon?
produced in pancreas and helps release glucose from liver
bile?
produced by liver and stored in gallbladder and helps breakdown fat in small intestines
how does the parasympathetic nervous system relate to the digestive system?
by controlling the smooth muscle involved in mechanical digestion and movement of food
what absorbs nutrients along the stomach and intestines?
-blood vessels
what kind of enzymes are found within the salvia?
amylase and lipase to initiate chemical digestion of starch and lipids
what is chemical digestion?
process where enzymes break down food particles into simple chemicals that can be used by the body
swallowed aka
deglutition
where is the gastric sphincter?
before the stomach, this sphincter pushes bolus to the stomach
what prevents reflux of food back into the esophagus?
esophageal (cardiac) sphincter
what are the three main secretions of the stomach?
-mucus which lines the stomach
-hydrochloric acid creates an acidic environment
-pepsinogen is converter into pepsin which is an enzyme that helps chemically digest proteins in acidic environment
what is pepsin?
an enzyme that helps chemically digest proteins in this acidic environment of the stomach, activated by hydrochloric acid
parts of the small intestines in order:
-duodenum
-jejunum
-ileum
how and where is chyme neutralized?
within the duodenum through bicarbonate. duodenum receives alkaline bile juices from the gallbladder which helps neutralize acidic chyme
brush border enzymes are produced by? include?
produced by the duodenum, includes proteases, lactase and other disaccharidases and bicarbonate
what does protease do?
lactase?
-protease: break down protein
-lactase: helps to digest lactose, produced by cells that line the walls the duodenum
what does the ileum mostly contain?
villi and microvilli
what does blood carry?
where does it pass from? to? through? allowing? convert? metabolize? store?
blood carries nutrients which passes from the small intestine to the liver through the hepatic portal duct, allowing enzymes to deaminate amino acids, convert ammonia to urea, metabolize consumed toxins and store glucose as glycogen
what projects from the colon?
vermiform appendix at the junction of small and large intestines
what vitamin is absorbed in the large intestines?
vitamin K
what hormone induces hunger?
ghrelin
leptin causes?
hormone that causes sensation of satiety (feeling full)
insulin induces? glucagon stimulates?
induces cellular uptake of glucose
stimulates breakdown of stored glycogen
what are enzymes?
proteins produced by the body that catalyze and speed up reactions
bile aids in?
chemical that aids in digestion by the breakdown in lipids or fats which is released by the gallbladder
