A&P Chapter 24 digestive
The essential functions of the liver include
- metabolic regulation. - hematological regulation. - bile production. - albumin production for blood osmotic pressure
Enterogastric reflexes
-inhibit gastric secretions -are triggered by chyme entering the duodenum -involve the enteric nervous system -inhibit gastric motility
How is the muscularis externa modified in the stomach?
there is an additional third oblique layer of smooth muscle
During the cephalic phase of gastric secretion,
there is an increased flow of action potentials along the vagus nerve to the stomach
An obstruction of the common bile duct often results in
undigested fat in the feces
Carbohydrate digestion begins in the
Mouth
An enzyme that digests proteins into peptides is
Trypsin
A drug that blocks the action of carbonic anhydrase in parietal cells would result in
a higher pH during gastric digestion
Each of the following organs is a component of the digestive tract, except the a.)colon. b.)bladder. c.)esophagus. d.)pharynx. e.)stomach.
b.)bladder
The part of the stomach that functions as a mixing chamber for food and secretions is the
body
Which of these effects on digestion is not produced by the parasympathetic nervous system? a.)increased saliva production b.)increased mucous secretion c.)decreased acid secretion d.) increased peristalsis
c.) decreased acid secretion
An intestinal hormone that stimulates the gallbladder to release bile is
cholecystokinin.
Which of these descriptions best matches the term myenteric plexus?
coordinates activity of muscularis externa
Lipid-soluble vitamins cross the digestive epithelium primarily by _________.
diffusion
The pylorus empties into the
duodenum
The Kupffer cells of the liver a.)destroy RBCs. b.)present antigens. c.)destroy bacteria. d.)are phagocytic. e.)All of the answers are correct.
e.) all of the answers are correct
The pancreas produces a.)sodium bicarbonate. b.)nucleases. c.)lipases and amylase. d.)peptidases and proteinases. e.)All of the answers are correct.
e.)all of the above
An intestinal hormone that stimulates mucus secretion by the submucosal duodenal glands is
enterocrinin.
The gastric phase of gastric secretion is triggered by the
entry of food into the stomach
Bile is stored in the
gallbladder
An intestinal hormone that stimulates the release of insulin from the pancreatic islet cells is
gastric inhibitory peptide GIP
An intestinal hormone that stimulates gastric secretion is
gastrin
G cells of the stomach secrete
gastrin
The stomach is different from other digestive organs in that it
has three layers of muscle in the muscularis externa
The activities of the digestive system are regulated by
hormones, parasympahetic and sympathetic neurons, the contents of digestive tract, intrinsic nerve plexus
Parietal cells secrete
hydrochloric acid
Plicae and intestinal villi
increase the surface area of the mucosa of the small intestine.
The pH of the blood in gastric veins
is greater during digestion of a large meal than following a 24-hour fast
Most chemical digestion and nutrient absorption is performed in the __________.
jejunum
If digestion of a carbohydrate results in equal amounts of glucose and galactose, this carbohydrate is probably
lactose.
What organ is primarily responsible for water absorption?
large intestine
Which organ is responsible for dehydration and compaction of indigestible materials?
large intestine
Powerful peristaltic contractions that occur a few times each day in the colon are called
mass movements
Digestion refers to the
mechanical and chemical breakdown of food.
The cells in the gastric mucosa near the openings of the gastric pits largely specialize in secreting __________.
mucus
The cephalic phase of stomach function is an example of the __________ system interacting with the digestive system.
nervous
The enzyme alpha-amylase that digests polysaccharides is secreted by the __________.
pancreas
The exocrine portion of the pancreas is composed of
pancreatic acini
Which digestive juice contains enzymes that breakdown carbohydrates, lipids, and proteins?
pancreatic juice
Increased secretion by all the salivary glands results from
parasympathetic stimulation
Chief cells secrete
pepsinogen
The enzyme amylase digests
polysaccharides
The serous membrane that lines the peritoneal cavity
prevents irritation, lubricates the cavity, decreases friction, secretes peritoneal fluid
The enzyme pepsin digests
proteins
Functions of the large intestine include
resorption (absorption) of water and compaction of feces.
The intestinal hormone that stimulates the pancreas to release a watery, bicarbonate-rich fluid is
secretin
Hydrochloric acid from the stomach is neutralized in the small intestine by:
sodium bicarbonate from the pancreas
The stomach secretes the hormone ghrelin which functions to
stimulate hunger
Which of the following is true regarding lactose intolerance?
the intestinal crypts are not producing the enzyme lactase