A&P Chp 20 Digestive System

our salivary glands secrete how much saliva daily?

1 liter

each day the pancreas secretes _____ of pancreatic juice, essentially digestive enzymes and an alkaline fluid, into the small intestine

1.5 liters

about ______ of residue consisting of undigested food, sloughed off epithelial cells, minerals, salts, and bacteria, enter the _____ intestine each day.

500ml, large

proteins are complex molecules made up of folded and twisted chains of _____ _____ linked together by ____ _____.

amino acids, peptide bonds

the digestive process begins in the mouth, where salivary glands secrete the enzyme ______

amylase

enzymes contained in saliva begin the digestion process: _____ breaks down starch while ______ begins the digestion of fat.

amylase, lipase

where is the pancreas located?

behind the stomach

flow of blood through the liver step 3

blood filters through the sinusoids, allowing cells to remove nutrients (such as glucose, amino acids, iron, & vitamins) as well as hormones, toxins, & drugs. the lover secretes clotting factors, albumin, & glucose into the blood for distribution throughout the body

saliva moistens food and transforms it into a mass called _____ that can be swallowed easily.

bolus

digestion

breaks down food physically and chemically, and transforms it into a substance that cells can use

flow of blood through the liver step 6

canaliculi carry bile secreted by the hepatic cells and ultimately drain into the right and left hypatic ducts

portal vein

carries oxygen-poor but nutrient-rich blood from the digestive organs and spleen to the liver

internal sphincter

composed of involuntary smooth muscle

external sphincter

composed of voulntary skeletal muscle

soft palate

consists of mostly skeletal muscle; forms an arch between the mouth and the nasopharynx

just below the _____, the digestive tube expands to form the ____, a muscular sac whose primary function is to _____ _____.

diaphragm, stomach, store food

the stomach prepares food for ______ (most of which occurs in the intestines)

digestion

while enzymes in the stomach partially digest protein as well as small amounts of starch and fat, most of the _______ ______ and the absorption of ____, takes place in the _______. ____ is also absorbed mostly by the small intestine.

digestion process, nutrients, intestine, alcohol

bile reaches the gallbladder through a series of _____. it leaves the liver by the right and left _____ ducts. these two ducts converge to form the _____ _____ ____, which goes on to become the _____ ____ ____. bile from the liver first fills the common bile duct before backing up into the gallbladder through the cystic duct.

ducts, hepatic, common hepatic duct, common bile duct

the facilitate digestion, the fat must first be broken into small droplets, a process called ______.

emulsification

the pancreas is both an ____ and _____ gland. its endocrine function centers on ____ _____ that secrete insulin and glucagon

endocrine, exocrine, pancreatic islets

proteases

enzymes working in the stomach and small intestine to break peptide bonds

most of the pancreas consists of _______ tissue

exocrine

greater omentum

extends from the greater curvature of the stomach and hangs down over the small intestines like an apron; is a portion of the mesentery

lesser omentum

extends from the lesser curve of the stomach to the liver

T or F: the anus has only one sphincter

false

hard palate

formed by portions of the maxillae and the palatine bones; separates the mouth from the nasal cavity

the liver has _____ lobes, two of the lobes (the right and left lobes) are visible from an ____ view

four, anterior

the muscles of the stomach contract and churn to break food into small particles and to mix it with ______ _____.

gastric juice

hepatic artery

goes to the liver; delivers oxygenated blood from the aorta to the liver

as soon as the chyme enters the duodenum, pepsin is _____. at that point the pancreatic enzymes _____ ______ assumes the task of breaking the peptide bonds.

inactivated, trypsin, chymotypsin

flatus

intestinal gas

duodenum

is the first 10 inches of small intestine; is about 12 finger breadths long; receives chyme from stomach and pancreatic juice and bile; more digestive processes occur here than in any other part of intestine

once the fat is emulsified, pancreatic _____ (the main fat-digesting enzyme) begins to digest the fat.

lipase

the digestive tract includes the

mouth, pharynx, esophagus, stomach, large intestines, small intestines, rectum, & anus

flow of blood through the liver step 1

nutrient-rich blood from stomach and intestine enters the lobule through small branches of the portal vein

flow of blood through the liver step 2

oxygen-rich blood enters the lobule through small branches of the hepatic artery

in the stomach, the enzyme _____ hydrolyzes the peptide bonds between certain amino acids

pepsin

brush border enzymes called _____ break the remaining chains into individual amino acids, which are then absorbed into the bloodstream.

peptidases

flow of blood through the liver step 4

phagocytic cells called Kupffer cells remove bacteria, worn-out red blood vells, and debris from the bloodstream

haustra

pouches along the length of the large intestines

chyme leaves the stomach and enters the duodenum by passing through the _____ _____ which is in between the end of the stomach and before the duodenum

pyloric sphincter

_______ moistens the mouth and lubricates and protects the teeth; also plays an important role in taste

saliva

acinar cells

secrete digestive enzymes in an inactive form

parietal cells

secrete hydrocholric acid and intrinsic factor (which is necessary for the absorption of vitamin B12). hydrocholric acid helps kill microbes in swallowed food

mucous cells

secrete mucus, which protects the stomach lining and keeps the stomach from digesting itself

enteroendocrine cells

secrete the hormone ghrelin (which stimulates the hypothalamus to increase appetite)

saliva

secreted by salivary glands; a clear fluid consisting mostly of water; also contains mucus, an enzyme that kills bacteria, antibacterial compounds, electrolytes, and two digestive enzymes

chyme

semi-fluid mixture consisting of particles of food mixed with digestive juices

falciform ligament

separates the right and left lobes; also serves to anchor the liver

most chemical digestion and most nutrient absorption occurs in the _____ ____

small intestine

gallbladder

stores and concentrates bile

the liver is responsible for

storing and releasing glucose, processing vitamins and minerals, filtering toxins, and recycling old blood cells

hepatitis

swelling and inflammation of the liver; is a symptom rather than a condition; term often used to refer to a viral infection of the liver

hemmorrhoids

swollen, engorged veins in the anal canal

the accessory organs include the

teeth, tongue, salivary glands, liver, pancreas, gallbladder

ascites

the accumulation of fluid in the peritoneal cavity

secretin

the acid in chyme also triggers the duodenum to release secretin. secretin causes the bile and pancreatic ducts to release bicarbonate, which helps neutralize the stomach acid entering the duodenum.

cholecystokinin (CCK)

the arrival of chyme in the duodenum stimulates the duodenum to secrete the hormone CCK. CCK causes gallbladder contraction, forcing bile into the bile duct, and the release of pancreatic enzymes

flow of blood through the liver step 5

the central vein carries the processed blood out of the liver

where is stomach acid neutralized and pancreatic enzymes begin the task of chemical digestion?

the duodenum

mechanical digestion

the first phase of digestion; involves physically breaking down food into smaller pieces, beginning with chewing and continuing contractions and churning in the stomach and small intestines

what is the body's largest gland?

the liver

chemical digestion

the second phase of digestion uses digestive enzymes produced in the salivary glands, stomach, pancreas, and small intestines to break down food particles into nutrients (such as glucose, amino acids, and fatty acids) that cells can use

wheres the liver located?

the upper right abdomen, below the diaphragm

gastrin

this hormone from the stomach and the duodenum triggers both gallbladder contraction and pancreatic enzyme secretion. however, it exerts a much less powerful effect than does the CCK

hepatic lobules

tiny, six-sided cylinders; fill the interior of the liver; are the functional units of the liver

T or F: teeth help start digestion because they help chew food

true

the _____ nerve and the hormones cholecystokinin, gastrin, and secretin stimulate the secretion of bile and pancreatic juice.

vagus

the large intestines absorbs large amounts of _____ from the residue before passing the resulting waste material (______) out of the body

water, feces

peristalsis

wave-like muscular contractions that propel food toward the stomach once a bolus enters the esophagus