gastrointestinal (GI) system (NH)

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ascending colon

first main part of the large intestine

deglutition

the transport of a bolus of food or liquid from the mouth to the stomach

deglutition

swallowing of the food bolus

descending colon

part of the large intestine that passes downward on the left side of the abdomen toward the rectum

duodenum

first part of the small intestine

enzyme

substance that chemically breaks down food

esophageal sphincter

prevents reflux of food back into the esophagus

lower esophageal sphincter

opens when food enters the stomach

food enters the stomach at the what region?

cardiac region

ileum

absorbs any remaining nutrients that did not get absorbed by the duodenum or jejunum, in particular vitamin B12, as well as bile acids that will go on to be recycled

jejunum

purpose is to absorb sugars, amino acids, and fatty acids

pancreas

Large gland behind the stomach which secretes digestive enzymes into the duodenum

• has islets of langerhans

islets of langerhans

secrete into the blood the hormones insulin and glucagon

peristalsis

contraction of muscle in esophagus to move food through the body

pyloric sphincter

gateway between the stomach and the small intestine

rectum

final section of the large intestine, terminating at the anus

sigmoid colon

S-shaped last part of the large intestine, leading into the rectum

stomach

muscular organ located on the left side of the upper abdomen that receives food from the esophagus

transverse colon

middle part of the large intestine, passing across the abdomen from right to left below the stomach

salivary amylase

digests carbohydrates

bolus

saliva + chewed food

chyme

chewed food + gastric secretions

folds of stomach

rugae

bile does what

break down chyme, break down & emulsify fats

appendix

stores friendly bacteria which further break down food

gastrin

stimulates stomach & HCl secretion, aids stomach muscle contractions for digestion

pepsinogen + HCl

pepsin

pepsin

digests proteins

intrinsic factor

vitamin B12 absorption

gastric lipase

break down & digest fat

duodenum secretes

secretin, cholecytsokinin

cholecystokinin (CCK)

causes release of bile from gallbladder

secretin

promotes pancreatic secretions

pancreatic secretions

trypsin, chymotrypsin, pancreatic lipase, pancreatic amylase, bicarbonate ions

trypsin

digest proteins

chymotrypsin

digest proteins

pancreatic lipase

digests fats

pancreatic amylase

digest carbohydrates

bicarbonate ions

create alkaline environment

small intestine enzymes

lipase, protease, maltase, lactase, sucrase

protease

digest proteins

maltase, lactase, sucrase

breakdown carbohydrates into simple sugars

villi

increase surface area in small intestine

the large intestine absorbs what?

water and electrolytes

what helps with peristalsis in the large intestine?

tinea coli, haustra

mucus - bicarbonate barrier

protection of the gastric mucosa

adventitia (serosa)

protection

muscularis

helps with peristalsis

submucosa

highly vascular, absorption of nutrients

mucosa

secretive and absorption functions

what does HCl do?

activate pepsinogen

where is chyme formed?

stomach

where is bolus formed?

mouth

lymphs via lacteals absorb what?

fat, fat soluble vitamins

what has both skeletal muscle and smooth muscle?

esophagus

nasopharynx

begins behind the nasal cavity

oropharynx

middle part of throat, behind oral cavity

laryngopharynx

lowest part of throat

maltase digests

maltose

sucrase digests

sucrose

lactase digests

lactose

pancreas aids in?

chemical digestion