Digestive Mastering Study Guide for Test

Which layer of the alimentary canal is responsible for segmentation and peristalsis?
A. mucosa
B. serosa
C. submucosa
D. muscularis externa

muscularis externa

Which layer of the alimentary canal contains not only glands and blood vessels but also a nerve plexus that helps regulate digestive activity?
A. submucosa
B. muscularis externa
C. serosa
D. mucosa

submucosa

The __________ circulation drains all of the organs of the digestive system
A. visceral
B. hepatic portal
C. peritoneal
D. splanchnic

Hepatic Portal

Which layer of the digestive tract controls digestive propulsion?

A. mucosa
B.submucosa
C.muscularis externa
D. serosa

Muscular externa

Unitary smooth muscle is found in all hollow organs except for the heart. What structure do both heart muscle and unitary smooth muscle share that allows them to contract as a functional group?

A. T tubules
B. gap junctions
C. caveolae
D. epimysium

gap junctions

Which digestive process does NOT occur in the mouth?

A. segmentation
B. mechanical breakdown
C. ingestion
D. digestion

Segmentation

What control mechanism opens the gastroesophageal sphincter?

A. pH changes in the esophagus
B. detection of nutrients in the esophagus
C. constriction of the upper esophageal sphincter
D. peristalsis in the esophagus

peristalsis in the esophagus

Which of the following constitute a portal triad?

A. the porta hepatis
B. a bile duct along with a portal venule and arteriole
C. the hepatic artery and two hepatic veins
D. three lobules sharing a common central vein

a bile duct along with a portal venule and arteriole

Which of the following best describes the capillary wall structure found in the liver lobules?

A. The capillary walls have openings that allow large proteins and small cells to pass through.
B. The walls only allow water to pass through.
C. The walls have windows that allow small proteins to pass through but not cells.
D. The walls are continuous, only allowing small molecules and water to pass through.

The capillary walls have openings that allow large proteins and small cells to pass through.

What is a major function of pancreatic juice?

A. emulsifying fats by breaking them into smaller pieces
B. acidifying the contents of the stomach
C. acidifying the contents of the small intestine
D. neutralizing chyme entering the small intestine from the stomach

neutralizing chyme entering the small intestine from the stomach

Bile is produced by the __________ under hormonal influence of __________.

A. small intestine; CCK
B. gallbladder; CCK
C. liver; secretin
D. pancreas; secretin

liver; secretin

Which of the following is NOT a secretion of the pancreas?

A. insulin
B. bicarbonate
C. bile
D. nutrient enzymes

Bile

Which cells in the small intestine’s mucosa secrete mucus?

A. enteroendocrine cells
B. goblet cells
C. enterocytes
D. Paneth cells

Goblet Cells

Which of these best describes a lacteal?

A. a lymphatic vessel designed to help introduce fats to the blood
B. a deep pocket in the intestinal wall where endocrine and antimicrobial cells are located
C. a projection of the small intestine wall designed to increase surface area
D. special capillaries in the villi designed for absorbing food effectively

a lymphatic vessel designed to help introduce fats to the blood

Most absorption of nutrients occurs in the __________.

A. large intestine
B. jejunum
C. duodenum
D. stomach

JeJunum

Which of the following propels food residue over large areas of the colon three to four times a day?

A. defecation reflex
B. Valsalva’s maneuver
C. mass movement
D. haustral contractions

Mass movement

Which of the following is the primary physiological function of the large intestine?

A. primary digestion of food
B. nutrient absorption
C. mechanical breakdown of food
D. water absorption and feces elimination

water absorption and feces elimination

What type of blood capillary located in this sublayer is uniquely suited for absorption of nutrient material?

A. continuous
B. sinusoidal
C. fenestrated
D. lacteals

Fenestrated

Which of the following is the best illustration of the difference between metabolism and digestion?

A. Digestions must happen first for metabolism to follow it.
B. Digestion requires enzymes for it to take place while metabolism does not necessarily need or use them.
C. Digestion has a wide variety of chemical reactions while metabolism is restricted to only a few reaction types.
D. Metabolism comprises all of the chemical reactions preformed with in the body while digestion is only the breakdown of food within the GI tract.

Metabolism comprises all of the chemical reactions preformed with in the body while digestion is only the breakdown of food within the GI tract.

Peristaltic waves are ________.

A. segmental regions of the gastrointestinal tract
B. waves of muscular contractions that propel contents from one point to another
C. pendular movements of the gastrointestinal tract
D. churning movements of the gastrointestinal tract

waves of muscular contractions that propel contents from one point to another

All the chemical and mechanical phases of digestion and mechanical breakdown from the mouth through the small intestine are directed toward changing food into forms that can pass through the epithelial cells lining the mucosa into the underlying blood and lymphatic vessels.

A. True
B. False

True

The major means of propulsion through the alimentary canal is peristalsis.

A. True
B. False

True

The function of the hepatic portal circulation is to ________.

A. carry toxins to the kidney for disposal through the urinary tract
B. distribute hormones throughout the body
C. collect absorbed nutrients for metabolic processing in the liver
D. return glucose to the general circulation when blood sugar is low

collect absorbed nutrients for metabolic processing in the liver

From the esophagus to the anal canal, the walls of every organ of the alimentary canal are made up of the same four basic layers. Arrange them in order from the lumen.

A. submucosa, serosa, muscularis externa, and mucosa
B. muscularis externa, serosa, mucosa, and submucosa
C. mucosa, submucosa, muscularis externa, and serosa
D. serosa, mucosa, submucosa, and muscularis externa

mucosa, submucosa, muscularis externa, and serosa

Which of the following is not true of saliva?

A. cleanses the mouth
B. moistens food and aids in compacting of the bolus
C. contains acids which aid in chemical digestion
D. contains enzymes that begin the breakdown of carbohydrates

contains acids which aid in chemical digestion

The digestive function of the liver is to produce bile.

A. True
B. False

True

When swallowing, the epiglottis covers the larynx.

A. True
B. False

True

All but one of the following is a function of the low pH found in the stomach. Select the description below that does not reflect a role of stomach acid.

A. Many potentially harmful bacteria will be prevented entry to the small intestine by stomach acid.
B. The stomach’s acid catabolically breaks down foodstuffs in preparation for absorption.
C. Low pH converts pepsinogen to its active form, pepsin.
D. Stomach acid denatures proteins making the polypeptide chain more accessible to pepsin digestive enzymes.

The stomach’s acid catabolically breaks down foodstuffs in preparation for absorption.

Some antacid drugs block histamine receptors, resulting in reduction of the production and excretion of stomach acid. These drugs have the biggest effect on which of the following?

A. surface epithelial cells
B. mucous neck cells
C. chief cells
D. parietal cells

Parietal Cells

Generally the hormones secretin and cholecystokinin which are released by duodenal enteroendocrine cells will ________.

A. increases the output of stomach acid
B. slow the activities of the stomach
C. speed the activity of the jejunum
D. speed the churning of the stomach

Slow the activities of the stomach

Which of the following is not a factor that helps create the stomach mucosal barrier?

A. secretion of pepsinogen
B. thick coating of bicarbonate-rich mucus
C. tight junctions of epithelial mucosa cells
D. replacing of damaged epithelial mucosa cells

Secretion of pepsinogen

The bolus is liquefied in the ________ and it is now called chyme.

A. mouth
B. esophagus
C. small intestine
D. stomach

Stomach

Pepsinogen, an inactive digestive enzyme, is secreted by the ________.

A. chief cells of the stomach
B. goblet cells of the small intestine
C. parietal cells of the duodenum
D. Brunner’s glands

Chief cells of the stomach

Which vitamin requires intrinsic factor in order to be absorbed?

A. A
B. B12
C. C
D. K

B12

Chief cells ________.

A. produce HCl
B. produce mucin
C. produce gastrin
D. produce pepsinogen

Produce pepsinogen

What stomach secretion is needed to produce mature erythrocytes?

A. gastric lipase
B. intrinsic factor
C. pepsinogen
D. gastric amylase

Intrinsic factor

Select the correct statement about the regulation of gastric secretion.

A. Vagus stimulation of the stomach results in decreased secretion of gastric juice.
B. The presence of food in the stomach prevents hormonal control of gastric secretion.
C. Gastric secretion is enhanced by very low pH (below a pH of 2).
D. Gastric secretion can be stimulated before food has entered the mouth.

Gastric secretion can be stimulated before food has entered the mouth.

The ingestion of a meal high in fat content would cause which of the following to occur?

A. Bile would be released from the gallbladder to emulsify the fat in the duodenum.
B. Increased production of trypsinogen.
C. This type of food would cause secretion of gastrin to cease, resulting in faster gastric emptying.
D. The acid secretions from the stomach would be sufficient to digest this food but may cause heartburn.

Bile would be released from the gallbladder to emulsify the fat in the duodenum.

Some of the microbes that often invade other organs of the body are rarely found in the stomach. The reason for this is the presence of HCl.

A. True
B. False

True

Pepsinogen is the precursor to the gastric enzyme for protein digestion and is secreted by the parietal cells.

A. True
B. False

False

The only essential function of the stomach is to begin the digestion of proteins.

A. True
B. False

False

Fats significantly delay the emptying of the stomach through hormonal and neuronal signals.

True
False

True

The enterohepatic circulation reabsorbs bile salts in the distal portion of the small intestine (ileum). All of the following statements about the enterohepatic circulation are true except one. Select the statement below that is not true of the enterohepatic circulation?

A. All of the components of bile are recycled by this circulation.
B. The reabsorption of bile salts allows them to be reused within new bile.
C. Reabsorption of bile salts reduces the need to synthesize new bile salts.
D. Reabsorbing bile salts in the ileum gives more time to emulsify lipid and aid in their absorption within a greater length of the small intestine.

All of the components of bile are recycled by this circulation.

A doctor consulting a patient that recently has had their gall bladder removed would likely advise ________.

A. increasing unsaturated fats while eliminating trans fats in their diets
B. fewer, but larger meals
C. a low to no carb diet
D. eating foods that are low in fat

Eating foods that are low in fat

Select the best explanation for why protease enzymes are secreted in inactive forms.

A. The immunoglobulins protecting the digestive tract would be digested without proper regulation of protein digesting enzymes.
B. Inactive enzymes will simply be expelled with the feces if no protein is present in the digesting food, this will help to conserve energy.
C. The enzymes would digest each other if they were not properly regulated.
D. The cells producing inactive enzymes are themselves protected from the enzymes until they are safely within the lumen of the GI tract.

The cells producing inactive enzymes are themselves protected from the enzymes until they are safely within the lumen of the GI tract.

Choose the incorrect statement regarding bile.

A. Bile functions to emulsify fats.
B. Bile is both an excretory product and a digestive secretion.
C. Bile contains enzymes for digestion.
D. Bile functions to carry bilirubin formed from breakdown of worn-out RBCs.

Bile contains enzymes for digestion.

Hepatocytes do not ________.

A. detoxify toxic chemicals
B. store fat-soluble vitamins
C. produce digestive enzymes
D. process nutrients

Produce digestive enzymes

Digestion and absorption of which of the following would be affected the most if the liver were severely damaged?

A. carbohydrates
B. lipids
C. starches
D. proteins

Lipids

The pancreas has both an endocrine and an exocrine function.

True
False

True

The absorptive effectiveness of the small intestine is enhanced by increasing the surface area of the mucosal lining. Which of the following accomplish this task?

A. the vast array of digestive enzymes
B. villi, and microvilli
C. the rugae and haustra
D. Brunner’s glands and Peyer Patches

Villi, and microvilli

The function of the goblet cells is to ________.

A. secrete buffers in order to keep the pH of the digestive tract close to neutral
B. absorb nutrients from digested food and store them for future use
C. provide protection against invading bacteria and other disease-causing organisms that enter the digestive tract in food
D. produce mucus that protects parts of the digestive organs from the effects of powerful enzymes needed for food digestion

produce mucus that protects parts of the digestive organs from the effects of powerful enzymes needed for food digestion

The circular folds of the small intestine enhance absorption by causing the chyme to spiral, rather than to move in a straight line, as it passes through the small intestine.

A. True
B. False

True

The major role of absorption in the ileum is to reclaim bile salts to be recycled back to the liver.

A. True
B. False

True

Peyer’s patches are found in the submucosa of the distal end of the small intestine.
A. True
B. False

True

A ruptured appendix is life threatening because ________.

A. it is likely to cause massive infection of the abdominopelvic cavity
B. it is likely to cause severe internal bleeding
C. loss of the appendix’s function will cause an immune deficiency in the digestive system
D. the large intestine will no longer be able to receive digested material from the small intestine

it is likely to cause massive infection of the abdominopelvic cavity

Which of the following is not characteristic of the large intestine? It ________.

A. does not contain villi
B. is longer than the small intestine
C. exhibits external muscular bands called teniae coli
D. has pocket-like sacs called haustra

is longer than the small intestine

Bile salts bind at their hydrophobic regions to large fat globules within the chyme that enters the duodenum. Bile salts break up the fat globule into smaller fat droplets. This role of bile salts is best described as ________.

A. lipid digestion
B. lipid emulsification
C. lipid ingestion
D. lipid absorption

Lipid emulsificatiom

You have just eaten a meal high in complex carbohydrates. Which of the following enzymes will help to digest the meal?

A. cholecystokinin
B. gastrin
C. trypsin
D. amylase

amylase

Short-chain triglycerides found in foods such as butterfat molecules in milk are split by a specific enzyme in preparation for absorption. Which of the following enzymes is responsible?

A. lipase
B. amylase
C. chymotrypsin
D. pepsin

Lipase

Which of the following enzymes would be most active in the presence of a high concentrations of protein fragments?

A. lipase
B. dextrinase
C. trypsin
D. amylase

trypsin

Severe diarrhea can diminish potassium ion absorption.

True
False

True

dentify the functional area of the kidney at letter B.

Frontal section of the kidney.

A. renal pelvis
B.renal pyramid
C. renal cortex
D. renal column

Renal pyramind

The area at C will eventually drain urine into the __________.

Frontal section of the kidney.

A. collecting ducts
B. glomerulus
C. nephron
D. ureter

Ureter

Which arteries branch off the arcuate arteries?

Schematic of flow of blood into and through the kidney.

A. cortical radiate arteries
B. renal arteries
C. interlobar arteries
D. segmental arteries

Cortical radiate arteries

Which vessels are most intimate with the nephron loop and serve as a point to collect ions and water back into the blood?

Schematic of flow of blood into and through the kidney.

A. vasa recta
B. afferent arterioles
C. efferent arterioles
D. cortical radiate veins

vasa recta

Which of the following is NOT a function of the kidneys?

A. to maintain the proper balance between water and salts and between acids and bases
B. to regulate body fluid by controlling excretion from sweat glands
C. to metabolize vitamin D to its active form
D. to carry out gluconeogenesis during prolonged fasting

to regulate body fluid by controlling excretion from sweat glands

Where does the process of segmentation occur?

A. anus
B. small intestine
C. stomach
D. esophagus

Small intestine

How would you classify chewing food?

A. mechanical breakdown
B. digestion
C. ingestion
D. propulsion

mechanical breakdown

Which of the following functions is NOT correctly matched with its description?

A. propulsion: physical breakdown of ingested food in the GI tract
B. absorption; passage of digested nutrients into the blood or lymph
C. ingestion: intake of food nutrients
D. mechanical breakdown: churning movements in the GI tract

propulsion: physical breakdown of ingested food in the GI tract

Which organ of the digestive tract is the body’s major digestive organ?

A. large intestine
B. small intestine
C. liver
D. stomach

Small intestine

The __________ is the serous membrane that lines the abdominal organs.

A. omenta
B. parietal peritoneum
C. visceral peritoneum
D. mesentery

visceral peritoneum

Which of the following is NOT a function of saliva?

A. Saliva moistens food and helps compact it into a bolus.
B. Saliva dissolves food chemicals so that they can be tasted.
C. Saliva contains enzymes that begin the chemical breakdown of proteins.
D. Saliva cleanses the mouth.

Saliva contains enzymes that begin the chemical breakdown of proteins.

Which of the following is NOT a characteristic of the stomach?

A. The stomach produces a double-layered coat of alkaline mucus.
B. The stomach releases enzymes to digest carbohydrates.
C. The stomach mucosa is folded into rugae.
D. The stomach has three layers of muscle in the muscularis tunic.

The stomach releases enzymes to digest carbohydrates.

In the __________ phase of gastric secretion, chyme is moved into the duodenum.

A. cephalic
B. intestinal
C. gastric phase
D. hvreflux

Intestinal

The intestinal phase of stomach digestion is triggered by partially digested nutrients filling the pylorus.

A. True
B. False

False

Gastric juice does not typically cause a burning sensation within the stomach. But reflux of this gastric juice into the esophagus can cause a burning sensation. One reason why this occurs is that the esophagus ______.

A. secretes mucus that is not identical to stomach mucus
B. is internally lined by epithelial cells that are in direct physical contact with the contents of the esophagus
C. has enzymes that react with stomach acid to cause a burning sensation
D. None of the listed responses is correct.

secretes mucus that is not identical to stomach mucus

Which of the following is the major process or function that occurs in the stomach?

A. defecation
B. absorption
C. deglutition
D. mechanical digestion

Mechanical digestion

The __________ is the first segment of the small intestine.

A. ileum
B. jejunum
C. duodenum
D. colon

Duodenum

Which of the following is NOT a structural modification of the small intestine that increases surface area?

A. microvilli
B. villi
C. rugae
D. circular folds

Rugae

Which of the following is NOT a function of the large intestine?

A. absorption of electrolytes
B. production of intrinsic factor
C. absorption of water
D. absorption of vitamins

production of intrinsic factor

Bacteria that reside in the large intestine make vitamin C.

A.True
B. False

False

__________ can result if food passes too slowly through the large intestine.

A. Irritable bowel syndrome
B. Diarrhea
C. Colitis
D. Constipation

Constipation