Exam 3 (Ch 24)

Match the gastric phase on the left (1-3) with the correct description on the right (4-6): 1. intestinal phase 4. prepares stomach for arrival of food 2. gastric phase 5. stomach empties and decreases secretions 3. cephalic phase 6. stomach secretes juice and mixes food into chyme

1 and 5; 2 and 6; 3 and 4

Which structure controls the contraction of the muscularis externa?

10

Put the following steps of stomach acid production in the correct order starting with the reaction that requires an enzyme. 1. H2CO3 dissociates. 2. Chloride ion combines with H+ in the gastric lumen. 3. Water and CO2 combine to form carbonic acid. 4. H+ and bicarbonate ion are transported into the gastric lumen. 5. Cl- diffuses into the gastric lumen.

3, 1, 4, 5, 2

Put the following layers of the digestive tract wall in order from the lumen to the deepest layer. 1. lamina propria 4. digestive (mucous) epithelium 2. muscularis externa 5. serosa 3. submucosa 6. muscularis mucosae

4, 1, 6, 3, 2, 5

Which structure(s) help(s) the stomach to stretch as it fills with food?

9

The greater omentum is

a fatty sheet that hangs like an apron over the abdominal viscera

A drug that blocks the action of carbonic anhydrase in parietal cells would result in

a higher pH during gastric digestion

Mary had her stomach mostly removed to try to overcome obesity. As a result, you would expect Mary to be at risk for

abnormal erythropoiesis.

Functions of the stomach include all of the following except

absorption of triglycerides.

The digestive tract is also referred to as the

alimentary canal and the GI tract

Each of the following is a function of the liver except

antibody production

The part of the stomach that functions as a mixing chamber for food and secretions is the

body

An intestinal hormone that stimulates the gallbladder to release bile is

cholecystokinin

A feature of the digestive tract wall that increases surface area available for absorption is the

circular folds.

Identify the structure labeled "4."

circular muscle layer

The duodenal ampulla receives secretions from the

common bile duct and the pancreatic duct

Contraction of the muscle layer labeled "9" causes the digestive tract to

constrict

Which of the following descriptions best matches the term myenteric plexus?

coordinates activity of muscularis externa

A disease that attacks and disables the myenteric plexus would

decrease intestinal motility

Brunner glands are characteristic of the

duodenum

Submucosal glands that secrete mucus are characteristic of the

duodenum

An intestinal hormone that stimulates mucin production by the submucosal duodenal glands is

enterocrinin

The gastric phase of gastric secretion is triggered by the

entry of food into the stomach.

All of the following contain mucous cells in the epithelium except the

esophagus

Which of the following is not a function of the digestive system?

filtration

During deglutition, which of the following phases is not present?

gastric

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 hormone that stimulates secretion and contraction by the stomach is

gastrin

The term "alkaline tide" implies that the pH of the blood in gastric veins is

greater during digestion of a large meal than following a 24-hour fast.

Which of the following contains adipose tissue and provides padding for the anterior and lateral portions of the abdomen?

greater omentum

The stomach is different from other digestive organs in that it

has three layers of muscle in the muscularis externa.

Parietal cells secrete

hydrochloric acid

Peyer's patches are characteristic of the

ileum

The portion of the small intestine that attaches to the cecum is the

ileum

Circular folds and intestinal villi

increase the surface area of the mucosa of the small intestine.

During the cephalic phase of gastric secretion,

increased production of gastric juice occurs.

The middle segment of the small intestine is the

jejunum

The villi are most developed in the

jejunum

The layer of loose connective tissue that directly supports the digestive epithelium is the

lamina propria

Which layer of the digestive tract has a layer of areolar tissue that surrounds the muscularis mucosae?

lamina propria

Which organ is responsible for dehydration and compaction of indigestible materials?

large intestine

What provides access for blood vessels entering and leaving the liver?

lesser omentum

Distension of the gastric wall leads to secretion of histamines from the lamina propria. This is an example of ________ response.

local

Identify the structure labeled "3."

longitudinal muscle layer

Digestion refers to the

mechanical and chemical breakdown of food.

The ________ are double sheets of peritoneal membrane that suspend the visceral organs and carry nerves, lymphatics, and blood vessels.

mesenteries

The double-layer sheets of serous membrane that support the viscera are called

mesenteries

The ________ supports all but 25 cm of the small intestine and provides stability and limited movement.

mesentery proper

The lamina propria and mucous epithelium are components of the

mucosa

The esophagus has several variations from the standard plan of the GI tract. These include

muscularis externa has some skeletal muscle.

Contraction of the ________ alters the shape of the intestinal lumen and moves epithelial pleats and folds.

muscularis mucosa

Sandwiched between the layer of circular and longitudinal muscle in the muscularis externa is the

myenteric plexus.

Identify the structure labeled "10."

oblique muscle layer

Which of the following is not a pharyngeal muscle involved in swallowing?

omohyoid

Gastric pits are

openings into gastric glands.

The exocrine portion of the pancreas is composed of

pancreatic acini

Chief cells secrete

pepsinogen

Waves of muscular contractions that propel the contents of the digestive tract are called

peristalsis

Circular folds are

pleats in the lining of the small intestine

All of the following are true of the intestinal phase of gastric digestion except that it

precedes the gastric phase.

What is the function of the structure labeled "7"?

protection from bacteria

The enzyme pepsin digests

proteins

All of the following are true of the lining of the stomach except that it

recycles bile.

What is the function of the structure labeled "6"?

regulates gastric emptying

An enzyme secreted by the gastric mucosa of a newborn that coagulates milk proteins is

rennin

The intestinal hormone that stimulates the pancreas to release a watery, bicarbonate-rich fluid is

secretin

Which of the following descriptions best matches the term submucosal plexus?

sensory neural network

What type of epithelium covers the structure labeled "6"?

simple columnar

The stomach secretes the hormone ghrelin which functions to

stimulate hunger.

Which of the following descriptions best matches the term gastrin?

stimulates gastric secretion

The oral mucosa has ________ epithelium.

stratified squamous

The epithelium lining the oropharynx is

stratified squamous.

Large blood vessels and lymphatics are found in

submucosa

What is the layer labeled "3"?

submucosa

Sensory nerve cells, parasympathetic ganglia, and sympathetic postganglionic fibers can be found in the

submucosal plexus.

Muscles known as the pharyngeal constrictors function in

swallowing