Download Digestion Review

Digestive System: Anatomy Review
1.
List two main divisions of the digestive system.
1.
2.
_____________________
2.
_____________________
The four main layers of the digestive tract wall are:
1.
_____________________
2. ____________________
3.
_____________________
4. _________________
3.
Label the diagram below with the four main layers you listed in question 2.
4.
The mucosa includes a type of columnar ________that forms the inner lining of the lumen.
5.
Blood and lymph vessels of the mucosa are found in its ______ _______ connective tissue layer.
6.
The smooth muscle layer of the mucosa is called the ________ _______.
7.
The function of epithelial goblet cells is to secrete ________.
8.
_________ cells of the mucosa secrete hormones into the blood.
9.
Absorption of nutrients occurs through the mucosal epithelium and into either _______ or ______ vessels.
10.
Label the vessels you listed in question 9 in the diagram below.
11.
The muscularis mucosa has both ________ and _______ fibers that function in moving the villi to aid in digestion
and absorption.
12.
The built-in (intrinsic) network of nerve cells in the submucosa is the ______ ______.
1
13.
The two types of movements produced by contractions of the muscularis externa are ____________ and
____________.
14.
The network of neurons in between the two muscle layers of the muscularis externa is the ___________
___________.
15.
The mouth, with its ____ ____ epithelium, is involved in both chemical and ____ digestion.
16.
List the four regions of the stomach:
17.
1.
_____________________
3.
_____________________
2.____________________
4.____________________
List the three sheets of muscle in the stomach’s muscularis externa:
1.
_____________________
3.
_____________________
2._____________________
18.
Label the three sheets of muscle in the stomach’s muscularis externa in the diagram below.
19.
List, in order from the pylorus to the colon, the three regions of the small intestine:
20.
1.
_____________________
3.
_____________________
2.
_____________________
From largest to smallest, list the three modifications of the small intestine’s inner wall that function to increase
surface area:
21.
1.
_____________________
3.
_____________________
2. _____________________
Label two of the modifications of the intestine to increase surface area in the following diagram.
2
22.
The microvilli of the small intestine’s epithelial cells form the ______ border.
23.
The large intestine absorbs __________, __________, and ___________.
24.
Starting from the ileocecal valve, trace the path of undigested material through the large intestine.
25.
The anus is lined with ______ _______ epithelium.
26.
List the six sphincters of the digestive tract:
1.
_____________________
2.
_____________________
3.
_____________________
4.
_____________________
5.
_____________________
6.
_____________________
27.
The single digestive function of the liver is to produce _____.
28.
The main digestive enzyme–producing organ in the body is the ______.
29.
Three pairs of _____ _____ function to moisten food in the mouth.
Digestive System: Control of the Digestive System
1.
List the primary two mechanisms that control the motility and secretion of the digestive system.
1.
2.
_____________________
2.
_____________________
List the three phases of digestive system processes:
1.
_____________________
3.
_____________________
2.
_____________________
3.
The ___________ nerve triggers the responses during the cephalic phase of digestion.
4.
The stimulation of __________ receptors triggers the gastric phase of digestion.
5.
List the four main responses during the intestinal phase of digestion:
3
6.
1.
_____________________
2. _____________________
3.
_____________________
4. _____________________
The small intestine typically________.
a.
b.
c.
7.
slows gastric emptying
accelerates gastric emptying
has no effect on gastric emptying
The ____________ and _________ ____________ nerves carry parasympathetic impulses to the enteric nervous
system.
8.
Sympathetic NS innervation of the digestive tract is via ____________ fibers.
a.
b.
9.
preganglionic
postganglionic
The ___________ and ______________ plexuses are the two components of the enteric nervous system.
10.
Digestive system reflexes that involve the brain are called ______ _______.
11.
A meal consisting largely of fatty foods will take __________ to digest than a meal consisting mainly of starchy
foods.
a.
12.
a longer time
b.a shorter time
c. the same time
All preganglionic ANS fibers release _______, while only postganglionic fibers of the sympathetic division release
_________.
13.
Which of the following neurotransmitters stimulates smooth muscle contraction in the digestive tract?
a.
VIP
b.orepinephrine
c.NO
d. ACh
14.
______ slow intestinal motility and cause the pyloric sphincter to contract.
15.
List five peptide hormones of the GI tract:
16.
17.
1.
_____________________
3.
_____________________ 4._____________________
_____________________
5. _____________________
List four functions of duodenal CCK.
1.
_____________________
3.
_____________________
2. _____________________
4.
_____________________
Secretin stimulates gastric HCl secretion.
a.
18.
2.
True
b.
False
GIP stimulates the pancreas to secrete_________.
4
19.
______ stimulates motility of the intestine, thereby moving its contents toward the terminal ileum.
20.
_______ occurs when the combined action of two hormones is greater than the sum of their individual effects.
Digestive System: Motility
1.
The process by which food is received into the GI tract via the mouth is called _____________________.
2.
The esophagus is digestive in function.
a.
3.
True
b.
False
Swallowing has both voluntary and involuntary components.
a.
True
b.
False
4.
The function of the epiglottis is to prevent a bolus from entering the _____.
5.
The first wave of contraction of the esophageal muscles is called ______ ______.
6.
If a food bolus does not make it all the way to the stomach, _________ peristalsis forces the bolus the remainder of
the way.
7.
Peristaltic contractions of the stomach occur about _____ times per minute when food makes it into the body and
fundus.
8.
The frequency of peristaltic contractions is regulated by ________ cells.
9.
Gastric emptying would be slowed by which of the following?
a.
c.
e.
fats in the duodenum
hypertonic solutions in the duodenum
all of the above
b. acids in the duodenum
d. distention of the duodenum
10.
______ regulate gastric juice secretion during the cephalic phase.
11.
*Now would be a great time to fill in the interactive table on page 7 of the Motility topic.
12.
The cephalic phase of digestion is regulated by short reflexes.
a.
True
b. False
13.
The _______ nerve carries electrical signals from the brain to the stomach.
14.
The hormone ______ regulates gastric secretion during the gastric phase of digestion.
15.
Gastric motility ________ as the stomach begins to receive food.
16.
The hormone ______ released by the duodenum causes gastric motility to decrease when fats are present in the
duodenum.
17.
The hormone _______ causes the gallbladder to contract and release bile into the small intestine.
5
18.
The ________ reflex describes the communication between the intestine and the stomach.
19.
Sympathetic nervous system stimulation ________ digestive system activity.
20.
The motility process illustrated below is _________.
21.
Segmentation moves chyme in only one direction.
a.
True
b. False
22.
The frequency of segmentation contractions is greatest in the _____.
23.
_____ reflexes stimulate the ileum to increase activity when food is in the stomach.
24.
The hormone _________ causes the ileocecal sphincter to relax during the gastric phase.
25.
During the interdigestive period, _______ _______ _______ occur about once every 90 minutes to move undigested
materials toward the terminal ileum.
26.
Migrating motility complexes are controlled by the central nervous system.
a.
27.
True
b. False
List the two major functions of the large intestine:
1.
_______________________
2.
_______________________
28.
Pockets formed by the contractions of the transverse and descending colon musculature are called ___________.
29.
Sustained, intense propulsive peristaltic contractions of the large intestine are called __________ ___________.
30.
Which of the following is under voluntary control?
a.
31.
internal anal sphincter
b. external anal sphincter
Only about _______ ml of the 500 ml of chyme that entered the colon is voided as feces.
6
32.
Place the following labels on the large intestine figure below:
cecum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum, haustra, appendix
33.
The ________ reflex stimulates mass movements of the colon.
34.
List three emotions or sensations that may produce constipation.
1.
_________________________
3.
_________________________
2.
_________________________
34.
The vomiting reflex is coordinated in the ___________ ___________.
35.
Which of the following is not typically a stimulus for the vomiting reflex?
a.
b.
c.
d.
noxious chemicals
abnormal vestibular stimulation
sudden injury to the testes
sleep
Digestive System: Secretion
1.
Of the approximately 9.0 L of fluids contained in the digestive tract daily, only __________ L are eliminated with the
feces.
2.
Of the approximately 800 g of food ingested during a typical day, only about ____ g are eliminated as undigested
food in the feces.
3.
Label the parotid, submandibular, and sublingual salivary glands in the figure below:
7
4.
List the four major functions of saliva.
1.
_________________________
2.
_________________________
3.
_________________________
4.
_________________________
5.
Parasympathetic innervation to the salivary glands is transmitted by cranial nerves number _______ and _______.
6.
Both the sympathetic and parasympathetic divisions of the ANS stimulate the salivary glands.
a.
7.
True
b.
False
________ division innervation stimulates watery, enzyme-rich saliva secretion, whereas ________ division
innervation stimulates a mucus-rich, more viscous saliva secretion.
8.
Label the figure below with the terms parasympathetic and sympathetic.
9.
The esophagus secretes digestive enzymes.
a.
10.
True
b. False
The four main components of gastric juice are:
1.
_________________________
2.
_________________________
3.
_________________________
4.
_________________________
11.
Gastrin is released from the ______ region of the stomach.
12.
Place the following labels on the figure below: parietal cell: HCl + IF, chief cell: pepsinogen, paracrine cell:
histamine, mucus neck cells
13.
Gastrin-producing G cells are found in the gastric glands located in the ________ region of the stomach.
8
14.
List the only two substances that are absorbed across the stomach’s mucosal epithelium:
1.
_________________________
2.
_________________________
15.
HCl in the stomach produces a pH of between ________ in the luminal fluid.
16.
Which of the following is a function of HCl in the stomach?
a.
c.
e.
17.
activates pepsinogen
kills most bacteria
All of the above are functions of HCl.
b. breaks down cell walls
d. denatures proteins in food
Without _______ _______, vitamin B12, necessary for normal RBC development, can not be absorbed by the
intestine.
18.
List the two secretions that stimulate HCl release from parietal cells.
1.
_________________________
2._________________________
19.
During the cephalic phase, _________ neural reflexes stimulate an increased production of gastric juice.
20.
Lipids in the intestine cause the release of the hormone _______, while acid in the intestine causes the release of
______.
21.
Match the following pairs of terms:
CCK and secretin—bicarbonate pancreatic juice and enzyme-rich pancreatic juice
22.
List the three major proteases (inactive forms) secreted by the exocrine pancreas:
1.
_________________________
3.
_________________________
2. _________________________
23.
Intestinal ________ converts (activates) trypsinogen into trypsin.
24.
The pancreatic hormone _______ regulates the absorptive state, while ______ regulates the postabsorptive state.
25.
List the four organic components of bile.
26.
1.
_________________________
2._________________________
3.
_________________________
4._________________________
Intestinal digestive enzymes that are embedded in the epithelial microvilli membranes are called ________ ________
enzymes.
27.
The intestinal hormone _____ causes contraction of the gallbladder and release of bile into the duodenum.
28.
_______ _______ protects the wall of the large intestine from mechanical damage and from damage by bacterial acid.
9
Digestive System: Digestion and Absorption
1.
2.
List the three major nutrient classes (a.k.a. macronutrients).
1.
_________________________
3.
_________________________
Which of the following carbohydrates is not a disaccharide?
a.
3.
2._________________________
maltose
b.lactose
c.starch
d. sucrose
Match the following pairs of molecules with their monomers by placing the number next to the matching letter:
a.
sucrose __________ b. maltose __________
c.starch ___________
d.
lactose __________
The monomers:
1. many glucose monomers
2. glucose + fructose
3. glucose + galactose
4. glucose + glucose
4.
The breakdown products (monomers) of proteins are __________ _________.
5.
The breakdown products of triglycerides include monoglycerides and _______ _________.
6.
Place the following labels on the diagram below:
maltose, maltotriose, limit dextrin
7.
Once food is acidified in the stomach, amylase continues to digest starch.
a.
True
b. False
8.
The digestive enzyme ________ begins the breakdown of proteins in the stomach.
9.
Pepsin is inactivated in the duodenum.
a.
True
b.False
10.
Pancreatic __________ is responsible for the majority of fat digestion.
11.
Most water and salt are absorbed in the colon.
a.
True
b. False
10
12.
The active transport of sodium is necessary for water absorption in the small intestine.
a.
True
b. False
13.
The final digestion of carbohydrates is accomplished with ______ ______ enzymes.
14.
Which of the following is not a brush border enzyme?
a.
15.
amylase
b.sucrase
c. dextrinase
d. glucoamylase
Place the following labels on the figure below:
luminal side, facilitated diffusion transporter, basolateral side
16.
17.
List the three major pancreatic proteases.
1.
_____________________
3.
_________________________
Only single amino acids are absorbed in the small intestine.
a.
18.
True
b. False
List the two main brush border proteases.
1.
19.
2._________________________
_________________________
2._________________________
List the two mechanisms that help to increase the surface area of lipids for subsequent digestion with pancreatic
lipase.
1.
_________________________
2._________________________
20.
Bile salts surround monoglycerides and free fatty acids to form tiny droplets called ________.
21.
Triglycerides combine with lipoproteins inside the intestinal epithelial cells to form __________.
22.
Chylomicrons exit the intestinal epithelial cells and then enter the ________ lymphatic capillaries.
23.
The colon epithelium produces substantial amounts of digestive enzymes.
a.
True
b.False
24.
Colic bacteria produce substantial quantities of ________ ____ as a by-product of their metabolism.
25.
List the three main substances that are absorbed in the large intestine.
1.
_____________
2. ____________________
3. _________________________
11
12