Chapter 23 (Lecture) Flashcards
1
Q
all GI tract movement stops and the gut appears to be paralyzed
A
ileus
2
Q
extreme dryness of the mouth
A
xerostomia
3
Q
grinding or clenching of the teeth
A
bruxism
4
Q
what is the effect of whole proteins being absorbed and seen by the immune systme
A
allergies
5
Q
produces lysozyme
A
paneth
6
Q
change in the epithelium of the lower esophagus from stratified squamous to a columnar epithelia
A
Barrett’s esophagus
7
Q
common causes of malabsorption
A
- impaired nutrient absorption
- anything that interferes with the delivery of bile
- anything that interferes with the delivery of pancreatic juice
- severe bacterial infections
8
Q
major site for nutrient absorption
A
small intestine
9
Q
which structure of the small intestine is known as the brush border
A
microvilli
10
Q
contains a large number of bacteria
A
large intestine
11
Q
bacterial flora in the large intestine produce
A
- vitamin K
- B vitamins
- CO2
12
Q
major site for nutrient absorption
A
small intestine
13
Q
swallowing is hindered or prevented
A
achalasia
14
Q
excess iron is deposited in the tissues, increasing skin pigmentation and the risk of hepatic cancer and liver cirrhosis
A
hemochromatosis
15
Q
may result form excessively high levels of fat in the blood or excessive alcohol ingestion, but most acute cases arise from gallstones that block the bile duct
A
pancreatitis
16
Q
abnormal accumulation of fluid within the peritoneal cavity
A
ascites
17
Q
a noncontagious, periodic inflammation of the intestinal wall now understood to be an abnormal immune and inflammatory response to bacterial antigens
A
IBD
18
Q
overeating followed by purging
A
bulemia
19
Q
difficulty swallowing
A
dysphagia
20
Q
brush border enzymes that act on disaccharides
A
sucrase, lactase, maltase
21
Q
collects nutrient rich blood from the GI tract and delivers it to the liver
A
hepatic portal circulation
22
Q
what structure of the small intestine contains the sphincter/valve that connects to the large intestine
A
ileum
23
Q
inflammation of the intestine
A
enteritis
24
Q
final product of carbohydrate digestion
A
monosaccharides
25
what causes the defection reflex
stretching of the rectal wall
26
first segment of the small intestine
duodenum
27
most water is absorbed in
small intestine
28
what type of breakdown would chewing food be classified as
mechanical breakdown
## Footnote
(segmentation, churning, mastication)
29
When we ingest large molecules such as lipids, carbohydrates, and proteins, they must undergo catabolic reactions whereby enzymes split these molecules. This series of reactions is called
digestion
30
# true or false:
All the chemical and mechanical phases of digestion 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.
true
31
Which layer of the alimentary canal is constructed from either stratified squamous or simple columnar epithelium?
mucosa
32
Which layer of the alimentary canal is responsible for segmentation and peristalsis?
muscularis externa
33
serous membrane that covers most digestive organs
visceral peritoneum
34
outermost layer of the walls of the intraperitoneal organs
serosa
35
sheets of peritoneal membrane that hold the digestive tract in place
mesentery
36
# true or false:
the peritoneum is the most extensive serous membreane in the body
true
37
components of splanchnic circulation
* celiac artery
* hepatic portal vein
* superior mesenteric artery
38
nervous control of gastric secretion is provided by
* vagus nerve
* enteric plexus
39
Your patient has had a total gastrectomy (removal of the stomach). What potential problem are you MOST concerned about
anemia
## Footnote
The parietal cells of the stomach produce intrinsic factor, which permits the absorption of vitamin B12, a nutrient required for the maturation of red blood cells. Unless your patient receives vitamin B12 replacement therapy, he or she will develop pernicious anemia.
40
what stimuli inhibits salivation
being stressed or frightened
41
how many total permanent teeth should an adult have, assuming none have been lost or removed
32
42
impacted wisdom teeth is a problem that is never observed in children because
they lack third molar teeth
43
which structures of the body play a part in swallowing
mouth, pharynx, and esophagus all take part in swallowing
44
where does the involuntary portion of swallowing takes place in
the pharynx
45
the voluntary phase of swallolwing takes place within
the mouth
46
what structure is found in the stomach but nowhere else in the alimentary canal
an oblique muscle layer
47
produced in the stomach and contributes directly to the absorption of vitamin B12
intrinsic factor
48
begins as chyme enters the duodenum
intestinal phase of gastric secretion
49
# true or false:
Chief cells secrete inactive pepsinogen in order to prevent acid erosion inside of the chief cells.
false
50
roles of stomach acid
* Stomach acid denatures proteins making the polypeptide chain more accessible to pepsin digestive enzymes.
* Low pH converts pepsinogen to its active form of pepsin, preventing the protease enzyme from digesting the cells that produce it.
* Many potentially harmful bacteria will be prevented entry to the small intestine by stomach acid.
51
# true or false:
The major stimulus for production of intestinal fluid is distention or irritation of the intestinal mucosa by hypertonic or acidic chyme.
true
52
# true or false:
most gastric ulcers are due to excessive production of HCl
false
53
which vessel delivers nutrient-rich blood to the liver from the digestive tract
hepatic portal vein
## Footnote
All blood from the digestive organs as well as the spleen is delivered to the liver in the hepatic portal vein before being returned to the general circulation.
54
secretion of the pancreas
* bicarbonate
* insulin
* nutrient digesting enzymes
55
why are protease enzymes secreted in active forms
The cells producing inactive enzymes are themselves protected from the enzymes until they are safely within the lumen of the GI tract.
56
functions of hepatocytes
* detoxify toxic chemicals
* store fat-soluble vitamins
* process nutrients
57
digestion and absorption of which type of molecule would be most affected if the liver were severely damaged
lipids
58
# true or false:
the pancreas has both an endocrine and an exocrine function
true
59
what cells in the small intestine's mucosa secrete mucus
goblet cells
60
first segment of the small intestine
duodenum
61
The absorptive effectiveness of the small intestine is enhanced by increasing the surface area of the mucosal lining. Which of the structures accomplish this task?
villi and microvilli
62
what propels food residue over large areas of the colon three to four times a day
mass movement
63
as wastes navigate the large intestine, which features do they pass through in order
right colic (hepatic), left colic (splenic), and sigmoid flexures
64
functions of the large intestine
* absorption of water
* absorption of electrolytes
* synthesis of vitamins
65
can result if food passes too slowly through the large intestine
constipation
66
characteristics of the large intestine
* exhibits external muscular bands called teniae coli
* does not contain villi
* it has pocket-like sacs called haustra
67
# true or false:
most nutrients are absorbed through the mucosa of the intestinal villi by active transport
true
68
which enzymes is/are responsible for the chemical breakdown of carbohydrates
amylase
69
carbohydrates are digested into
monosaccharides
70
You have just eaten a meal high in complex carbohydrates. Which enzyme will help to digest the meal?
amylase
70
Bile salts break up the fat globule into smaller fat droplets. This role of bile salts is best described as
lipid emulsification
71
* inorganic molecules needed by the body
* add strength to tissues
* most are ionized and act as electrolytes
minerals
72
* not used for energy
* most act as coenzymes
vitamins
73
water soluble vitamins
C, B complex
74
fat soluble vitamins
A, D, E, K
75
small amounts of DNA and RNA are broken down by what into sugars and bases
pancreatic nucleases and brush border nucleases
76
most abundant lipid in diet
triglycerides
77
functions of lipids
* energy source
* padding
* cholesterol
* phospholipids
78
* composed of glycerol and 3 fatty acid chains
* milk, cheese, butter, plant, and animal oils
lipids
79
vastly increases the surface area available to be attacked by pancreatic lipase
emulsification
80
small phospholipid bubbles that allow the products of fat digestion to get close to the surface of the mucosa of the villi
micelles
81
composed of the digestive tract through which food passes, and the accessory organs that add secretions to the digestive tract
digestive system
82
* a continuous tube leading from the mouth to anus
* consists of the oral cavity, pharynx, esophagus, stomach, small and large intestines, and anal canal
digestive tract / ailmentary canal
83
* teeth, salivary glands, liver, gallbladder, and pancreas
* secrete fluids and enzymes into the digestive tract
accessory organs
84
physical processes that take place in the digestive system
* ingestion
* mastication (chewing)
* propulsion (deglutition followed by peristalsis)
* mixing (segmental contractions in the SI
* transport (circulatory or lymphatic)
* elimination (defecation)
85
chemical processes of the digestive system
* secretions (mucus, water, enzymes)
* digestion (enzymes)
* absorption (nutrients through villi or lacteals)
* regulation (nervous - vagus, hormonal, local)
86
inflammation of the peritoneum
peritonitis
87
* serous membrane of the abdominopelvic cavity (visceral and parietal)
* layers separated by namesake cavity that contains serous fluid
peritoneum
88
* a sheet of two fused serous membranes from the body wall to the digestive organs
* provides a route for blood vessels, nerve, lymph vessels
* holds organs in place
mesentery
89
organs not suspended by mesentery are
retroperitoneal
## Footnote
pancreas, some SI and LI
90
* include the arteries from the celiac trunk and the mesenteric arteries
* also includes venous hepatic portal circulation
splanchnic circulation
91
92
* composed of three layers: the namesake epithelium, lamina propria, and namesake muscularis
mucosa
93
contains mucus glands
mucosal epithelium
94
loose connective tissue
lamina propria
95
thin smooth muscle
muscularis mucosa
96
moderately dense CT containing nerves, blood vessels, small glands; submucosal plexus made of parasympathetic ganglionic fibers
submucosa
97
* two major plexuses are myenteric and submucosal
* control much of the activities of the GI tract
* communicate w/ CNS via afferent visceral fibers and ANS sympathetic and parasympathetic fibers (motor)
* capable of acting on its own w/ little or no CNS oversight
enteric NS
98
arteries of splanchic circulation
* celiac trunk (hepatic a., splenic a., gastric a.)
* superior and inferior mesenteric a.
99
veins of splanchic circulation
hepatic portal system
100
digestive system typically receives about how much blood flow per minute
25% of total blood flow
101
* inner layer of muscularis
* in some places pinches to form sphincters
circular layer
102
outer layer of muscularis
longitudinal (smooth) layer
103
* outer CT layer
* provides support and protection, also known as the visceral peritoneum
* esophagus and some retroperitoneal organs lack this so it is known as adventitia
serosa
104
bound by lips, cheeks, tongue, and the hard and soft palates
oral cavity
105
dental formula
2123
* 2 incisors
* 1 canines
* 2 premolars
* 3 molars
106
controlled by intrinsic and extrinsic muscles, help control bolus formation
tongue
107
muscle that controls incisor biting
temporalis
108
muscle that controls molar biting
masseter
109
responsible for side to side motion
medial and lateral pterygoids
110
swallowing reflex begins here
pharynx
111
actively absorbed into the capillaries of the SI and go to the liver via the hepatic portal vein for processing and possible reassembly into other proteins
amino acids
112
proteins are broken down by
pepsin and HCl
113
polypeptides and some dipeptides are brken down by
pancreatic proteases
114
dipeptides are broken down by
brush border proteases
115
* 9 essential.11 nonessential amino acids are liberated from proteins
* from meat, fish, poultry, legumes, nuts, seeds, etc
* uses for building bones, muscles etc
* regulatory uses such as enzymes, transporters, hormones, etc
proteins
116
sources of carbohydrates
bread, cereal, pasta, candy, fruits, etc
117
indigestible starches
fiber
118
blood sugar
glucose
119
isomers of glucose
galactose and fructose
120
polysaccharides
starch (plants), glycogen (muscle)
121
disaccharides
sucrose, maltose, lactose
122
monosaccharides
fructose, galactose, glucose
123
absorbed by facilitated diffusion
fructose
124
absorbed in the capillaries in the intestines and sent to the liver via the hepatic portal vein
glucose
125
actively cotransported with sodium ions
glucose and galactose
126
* process is started in the mouth, continues in the stomach and SI
* a catabolic process in which large complex molecules are broken down into monomers and accomplished by the action of enzymes secreted from accessory glands and from the digestive tract itself
chemical digestion
127
the name for the enzymatic breakdown of food molecules
hydrolysis
128
a substance in food that is used to promote normal growth, maintenance, and repair
## Footnote
includes: carbs, proteins, fats, vitamins, minerals, and water
nutrients
129
perfect conditions for gallstones
5 Fs
Fair, FAT, Forty, Female, Fertile
130
neutralizes the acidic chyme coming out of the stomach
alkaline pancreatic juice
131
pancreatic secretions are regulated by
intestinal hormones and the vagus nerve
132
opening into the small intestine
major duodenal papilla
133
pancreatic duct joins common bile duct at
hepatopancreatic ampulla
134
digestive enzymes + bicarbonate ion
pancreatic juice
135
* site of hiatial hernias
* LUQ of abdomen, usually 15-25 cm long; can hold upwards of 2-4 L of food when filled
stomach
136
sites of omentum attachment
lesser and greater curvature
137
produce insulin and glucagon
pancreatic islet cells
138
pancreatic enzymes are produced by
acinar cells
139
stores and concentrates bile, releasing it upon a signal from the duodenum
gallbladder
140
aid in cholesterol excretion and emulsify lipids
bile salts
141
buffer duodenal contents
bicarbonate ions
142
* 4 lobes
* processes nutrient laden blood, manufactures bile, and secretes substances like angiotensinogen and albumin
* extracts nutrients from blood and sends bile to the gallbladder for storage
liver
143
secrete saliva containing mucin and salivary amhylase to initiate starch digestion
salivary glands
144
functions of the LI
* consolidates and moves unusable fecal material out of the body
* site of vitamin B and K manufacture by bacterial flora
* reclaims water and electrolytes from undigested food
* mass movements occur 3-4x a day to facilitate the movement of fecal material
145
controls the flow of material between the small and large intestines
ileocecal valve
146
chemical secretions of the stomach
* mucus (protection)
* HCl (decrease pH)
* intrinsic factor (vitamin B12)
* pepsinogen (pepsin)
147
regulation of gastric secretions (cephalic phase)
* Stimulated by sensations of taste, smell, and thoughts of food, chewing, and swallowing.
▪ The vagus carries this information to the nerves within the stomach wall.
▪ These Parasympathetic nerves in the stomach wall release ACH and this stimulates thenrelease of gastrin - which comes back around to stimulate additional release of pepsinogen
and HCL by the stomach.
148
secrete mucus
mucus neck cells
149
secretes HCl, intrinsic factor
parietal cells
150
secretes pepsinogen
chief cells
151
secrete regulatory hormones such as gastrin, histamine, endorphins, serotonin, CCK, etc
endocrine cells
152
* triggered by: stomach distention, amino acids and proteins in stomach + rising pH in stomach due to food
* causes local receptors to trigger reflexes and release more gastric secretions
* gastrin released in a positive feedback loop
gastric phase
153
regulation of gastric secretions phase
1. cephalic phase
2. gastric phase
3. intestinal phase
154
* chyme released into the duodenum, stimulates both neural and hormonal mechanisms
* as long as pH remains >3 gastric secretions are continued with gastrin being released fro the duodenum and causing the stomach to continue its secretions
intestinal phase
155
main cells of the liver that process nutrient laden venous blood
hepatocytes
156
liver attached to diaphragm via
falciform ligament
157
hexagonal in appearance, are the smallest functional units of the liver
lobules
158
stores, concentrates bile which is released upon a signal from the duodenum (CCK)
gallbladder
159
small pouches of visceral peritoneum filled with adipose tissue
epiplotic appendages
160
small sacs, caused by bunching of smooth muscles
haustra
161
muscularis layer reduced to 3 longitudinal bands
teniae coli
162
can result from water not being reclaimed from fecal matter
diarrhea
163
hydrolytic digestion via enzymes in SI
digestion
164
active or passive transport across the epithelium of SI
absorption
165
physical processes that take place in the SI
segmentation and peristalsis
166
products of lipid digestion are absorbed by
lacteals
167
how are the products of proteins and carbohydrate digestion absorbed
absorbed into submucosal capillaries in submucosal layer
168
common bile duct + pancreatic duct
hepatopancreatic ampulla
169
hydrolytic enzymes are bound to the microvilli to effect digestion
brush boder enzymes
170
part of the SI that is responsible for absorption and compaction
ileum
171
part of the SI that continues chemical digestion and absorption
jejunum
172
part of the SI that does the majority of chemical digestion
duodenum
173
inhibits gastric secretions but also the secretions of the pancreas and gall bladder in order to. digest fats
cholecystokinin (CCK)
174
inhibits gastric secretions when there are fatty acids present in SI
gastric inhibitory peptide (GIP)
175
released when SI becomes too negative and inhibits gastric secretions
secretin
