Exam 6 Digestive System Flashcards
taking in food
ingestion
digestion
breaking down food into nutrient molecules
movement of nutrients into the blood
absorption
defecation
excretes to rid the body of indigestible waste
alimentary canal (GI tract)
continuous, coiled, hollow tube that runs from stomach to anus
functions are chewing of food
tongue mixes chewed food with saliva
tongue initiates swallowing
taste buds on the tongue allow for taste
mouth
serves as a passageway for foods, fluids, and air
pharynx
oropharynx
posterior to oral cavity
laryngopharynx
below the oropharynx and continuous with esophagus
2 skeletal layers in pharynx
longitudinal outer layer
circular inner layer
10 inches long, runs from pharynx to stomach through the diaphram
esophagus
peristalsis
slow rhythmic squeezing
conducts food by peristalsis to stomach
passageway for food only
esophagus
Innermost to outermost layers of tissue
mucosa
submucosa
muscularis externa
serosa
Mucosa
small amount of connective tissue
scanty smooth muscle layer
lines the cavity
submucosa
soft connective tissue with blood vessels, nerve endings, mucosa-associated lymphoid tissue, and lymphatic cells
Muscularis externa (smooth muscle)
inner circular layer
outer longitudinal layer
Serosa
contains fluid producing cells
left side of the abdominal cavity
food enters at the cardioesophageal sphincter from the esophagus
food empties into the small intestine at the pyloric sphincter
stomach
regions of the stomach
cardial
fundus
body, greater and lesser curvature
pylorus
how much food can the stomach stretch to hold?
4 L or 1 gallon
rugae
internal folds of the mucosa present when stomach is empty
lesser omentum
extends from the liver to the lesser curvature of the stomach
greater omentum
covers the abdominal organs
fat insulates, cushions, and protects abdominal organs
what is intrinsic factor from gastric juices needed for?
absorption of vitamin B12 in the small intestine
functions of the stomach
temporary storage for food
site of food breakdown
chemical breakdown of protein begins
delivers chyme to the small intestine
chyme
processed food
the body’s major digestive organ
longest portion is 2-4 m or 7-13 ft long
site of nutrient absorption of the blood
muscular tube extending from the pylori sphincter to the ileocecal valve
small intestine
subdivisions of the small intestine
duodenum
jejunum
ileum
where does chemical digestion begin?
small intestine
enzymes in the small intestine
produced by intestinal cells and pancreas
carried to the duodenum by pancreatic ducts
bile in the small intestine
produced by the liver
enters the duodenum via the bile duct
location of where the main pancreatic duct and bile ducts join
hepatopancreatic ampulla
structural modifications of the small intestine
increased surface area for food absorption
villi, microvilli, and circular folds
collections of lymphatic tissue
located in submucosa of the small intestine
increase in number towards the end of the small intestine
Peyer’s patches
large in diameter, but shorter in length than small intestine
extends from the ileocecal valve to the anus
large intestine
subdivisions of the large intestine
cecum
appendix
colon
rectum
anal canal
cecum
sac-like first part of the large intestine
hangs from the cecum
accumulation of lymphoid tissue
appendix
external anal sphincter
formed by skeletal muscles and is voluntary
internal anal sphincter
formed by smooth muscles and is involuntary
3 pairs of salivary glands
parotid glands
submandibular glands
sublingual glands
mixture of mucus and serous fluid
saliva
saliva contains:
salivary amylase
lysozymes
found posterior to the parietal peritoneum
extends across the abdomen from spleen and duodenum
produces a wide spectrum of digestive enzymes that break down food
pancreas
fluid introduced in pancreas with enzymes that neutralizes acidic chyme from stomach
alkaline fluid
hormones produced by the pancreas
insulin and glucagon
largest gland in the body, right side under diaphragm
digestive role is to produce bile
liver
leaves the liver through the common hepatic duct and enters duodenum through the bile duct
bile
yellow-green, water solution containing cholesterol, phospholipids, and electrolytes
bile
breaks down fats
bile
green sac found in a shallow fossa in the inferior surface of the liver
gallbladder
bile backed up for storage when no digestion is occurring
bile is concentrated by the removal of water
when fatty food enter the duodenum, spurts out stored bile
gallbladder
