Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Patho Summer Test #1 > Gastrointestinal Module #1 > Flashcards

Gastrointestinal Module #1 Flashcards

(179 cards)

Start Studying
1
Q

What are the layers of the GI tract (from inner to outer layers)?

A

Mucosa

Submucosa

Muscularis

Adventitious (serosa)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the muscosa layer made of?

A

Mucosa Epithelium

Lamina Propria

Muscularis Mucosae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can you find in the submucosa layer?

A

Glands

Associated Ducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the layers of the muscularis layer?

A

Circular Layer

Longitudinal Layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the adventitious (serosa) layer made of?

A

Connective Tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the enteric nervous system?

A

Intrinsic Nervous System of the GI tract

**considered part of the autonomic nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What influences the enteric nervous system?

A

Parasympathetic = excitatory

Sympathetic = inhibitory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is unique about the enteric nervous system?

A

Functions autonomously (w/o having to go up to the brain)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 3 Enteric Plexuses?

A

Submucosal Plexus (Meissner Plexus)

Myenteric Plexus (Auerbach Plexus)

Subserosal Plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where is the submucosal plexus located?

A

Located in submucosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the function of the submucosal plexus?

A

Secretion and absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where is the myenteric plexus located?

A

Between circular/longitudinal layers of the muscularis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the function of the myenteric plexus?

A

Motility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where is the subserosal plexus located?

A

Mesentery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does the subserosal plexus innervate?

A

ANS innervation of blood vessels and connective tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 3 general functional components of the enteric plexuses?

A

Sensory

Motor

Interneurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What do the sensory neurons of the enteric plexuses monitor?

A

Distention and chemical status of GI tract

**Sensory afferents via sympathetic nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do the motor neurons of the enteric plexuses control?

A

Motility of the gut wall

Smooth muscle of GI vasculature

Secretions of the mucosa/submucosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does the interneurons of the enteric plexuses do?

A

Communication between sensory and motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the definition (for this class) of appetite?

A

Hunger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the definition (for this class) of satiety?

A

Sensation of fullness/satisfied

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where are the 2 centers that control appetite and satiety located?

A

Hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the names of the centers that control appetite and what are they specifically controlling?

A

Lateral Center = Appetite

Medial Center = Satiety

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the stimuli of the lateral center (appetite center)?

A

Smell (CN1), Vsiual, Taste (CN7, 9), Hearing (CN8)

Physiological Depletion of nutrient/energy stores

Memory/Fantasy

Gastric Hormone = Ghrelin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Where is ghrelin released from?
Stomach
26
What is ghrelin known as?
Hunger Hormone
27
What is the function of the medial center (satiety center)?
Suppress appetite
28
What are the stimuli of the medial center (satiety center)?
GI Hormones released during food ingestion (CCK, GLP-1, etc) Leptin PYY Insulin
29
Where is leptin released from?
Fat Cells Chief Cells
30
Where is PYY released from?
Small Intestine after meal
31
What extrinsilically influences the enteric system?
Autonomic Nervous Center: Sympathetic System = nerves of sympathetic tract in thoracic and upper lumbar regions Parasympathetic System = Vagus Nerve and pelvic nerves of sacral plexus
32
How does the sympathetic system influence the enteric system?
Inhibitory effects on the GI tract: decrease peristalsis and secretions inhibit blood flow to GI tract
33
How does the parasympathetic system influence the enteric system?
Excitatory to GI Tract: increase peristalsis and secretions relax involuntary sphincters of GI tract facilitate blood flow to GI tract
34
What is the intrinsic regulation of the enteric system?
Can feedback on itself and function autonomously = "brain in the gut"
35
What are the specific functions of the enteric nervous system?
Control Motility Regulation of fluid exchange and local GI blood flow Regulation of gastric and pancreatic secretion Regulation of gastrointestinal endocrine cells Defense reactions Entero-enteric reflexes ENS/CNS interaction
36
How does the enteric nervous system control motility?
Peristalsis Sphincter Control Etc.
37
How does the enteric nervous system regulate fluid exchange and local GI blood flow?
Regulate permeability to ions thus influence fluid Influence vasodilation of BV Influence fluid secretion
38
How does the enteric nervous system regulate gastrointestinal endocrine cells?
Signal release of GI hormones (ie excessive seratonin released from GI walls = nausea/vomiting)
39
What are the entero-enteric reflexes?
Signaling system between regions of the GI tract
40
What are examples of the entero-enteric reflexes?
Gastric activity stimulating Si motility and releaxation of iliocecal valve Small intestine activity signals release of pancreatic enzymes
41
What is secreted in the mouth that is important for the GI tract?
Saliva
42
What controls the release of salivia?
BOTH parasympathetic and sympathetic systems stimulate salivary glands NOT CONTROLLED BY HORMONES!
43
What does saliva contain (8 things)?
Water Mucus Na+ Bicarbonate Chloride K+ Salivary Amylase Immunoglobulin A (IgA)
44
What is the function of bicarbonate in saliva?
Maintain pH in mouth to neutrolize bacteria (tooth decay)
45
What does salivary amylase do?
Begins first steps to break down (digest) carbohydrates
46
What is the purpose of IgA in saliva?
Prevent Infection
47
Where is the upper esophageal sphincter located?
Junction of lower pharynx and esophagus Approximately @ level of cricoid cartilage
48
What is the function of the upper esophageal sphincter?
Prevent air from entering esophagus during ventilation
49
Is the upper esophageal sphincter considered a "true" sphincter?
Yes
50
Where is the lower esophageal sphincter located?
Narrowing of esophagus proximal to junction of esophagus and stomach
51
What is the function of the lower esophageal sphincter?
Barrier to reflux (regurgiation) of acidic content of stomach
52
Is the lower esophageal sphincter a true sphincter?
No
53
So if the lower esophageal sphincter is not a true sphincter, how is it maintained?
Increased smooth muscle tone --> 20 mmHg
54
What happens to the lower esophageal sphincter smooth muscle tone during swallowing?
Relaxed by peristaltic waves
55
What are the 2 phases of swallowing?
Voluntary Phase (oropharyngeal phase) Involuntary phase (esophageal phase)
56
What happens during the voluntary phase (oropharyngeal phase) of swallowing?
Food broken down and tongue pushes bolus posteriorly Soft palate (superior constrictor muscles) contract to close nasopharynx Epiglottis closes of larynex/trachea
57
How long does it take for food to be pushed into the esophagus during the voluntary phase (oropharyngeal phase) of swallowing?
1 - 2 seconds
58
When does the involuntary phase (esophageal phase) of swallowing begin?
As bolus enters esophagus
59
When does the involuntary phase (esophageal phase) of swallowing end?
As bolus enters stomach
60
How long does the voluntary phase (esophageal phase) of swallowing last?
5 - 10 seconds
61
How is the bolus moved toward the stomach in the esophagus?
Peristalsis
62
What is peristalsis?
Coordinated contraction/relaxation of the longitudinal/circular muscles
63
How does the esophageal muscular pressure range?
Ranges from 35 - 85 mmHg
64
What is the esophageal pressure in the upper and lower esophagus?
60 - 80 mmHg
65
What is the esophageal pressure in the middle esophagus?
30 - 45 mmHg
66
What happens to food in the esophagus if contractions are < 30 mmHg?
Food residue may get stuck
67
What is the nervous system that controls peristalsis?
Vagus Nerve for both excitatory and inhibitory pathways (works to coordinate contraction/relaxation)
68
What are the bodily chemicals that control peristalsis?
ACh = excitatory NO = inhibitory
69
What is secondary peristalsis?
Involuntary wave
70
What would cause secondary peristalsis?
Food residue from ineffective primary peristalsis OR Bolus that is "stuck"
71
Describe what happens when bolus/food residue gets stuck in the esophagus and causes a distention
Feedback to: Constrict esophagus above distention Relax esophagus below distention Which pushes residue/bolus along
72
What happens when you are swallowing food?
Single swallow initiates esophageal peristaltic contraction that lasts 5 - 10 seconds follwed by short refractory period
73
After swallowing a bite of food, what does the short refractory period following peristaltic contraction do?
Inhibits ability to swallow second bite of food more frequently than 10 - 15 seconda
74
How often do you swallow when drinking a liquid?
Every 1 - 2 seconda
75
What is the name of the inhibitory reflex in your esophagus and what does that reflex do when you're drinking a liquid?
Deglutitive Inhibition (made w/ quick subsequent swallows) Prevents esophagus from ongoing contraction --> esophagus stays relaxed to allow more liquid to descend = gulping
76
What are the 3 factors that create the basal tone of the lower esophageal sphincter?
Myogenic Tone (independent of neural input) Excitatory Vagal Tone (Cholinergic - ACh) Inhibitory Vagal Tone (Nitrergic - NO)
77
What are some factors that increase lower esophageal sphincter pressure?
Vagus Nerve --> excitatory pathways of vagus nerve Gastrin Meds for GERD
78
Why does gastrin increase lower esophageal sphincter pressure?
Gastrin promotes acid secretion/motility so you need to keep LES closed to prevent acid reflex in esophagus
79
What are some factors that decrease lower esophageal sphincter pressure?
Vagus Nerve --> inhibitory pathways Hormones: progesterone, secretin, glucagon Fried fatty foods Tomatoes Citrus High Protein Diet Chocolate Peppermint Tobacco Alcohol Caffeine
80
What happens to cause GERD?
Decreased LES pressure and ineffective clerance mechanism of secondary peristaltic waves Chronic acid reflux reslts in in flammation/pain and eventual destruction of esophageal wall (esophagitis)
81
What are some causes of decreased lower esophageal pressure/risk factors for GERD?
Hiatal Hernia Pregnancy Excessive ETOH Tobacco Obesity
82
What is achalasia?
Rare disease in which lower esophageal sphincter fails to relax Causes pain with eating and drinking
83
What happens to cause achalasia?
Unknown exactly but it is a mechanical result of peristalsis of the esophageal musculature and the failure of the lower esophageal sphincter to relax
84
What is esophageal varices?
Severely dilated sub-mucosal veins in the esophagus **usually d/t portal hypertension
85
What can esophageal varices lead to?
Bleeding --> Chronic GI bleeding --> severe systemic consequences
86
What is Barrett's Esophagus?
Condition in which normal mature cells (esophageal squamous epithelium) lining the esophagus are replaced w/ abnormal cells (metaplastic columnar mucosa) d/t exposure to stomach acids
87
What is metaplasia?
1 mature adult cell type is replaced by another
88
What are the symptoms of Barrett's Esophagus?
"Heart Burn" **metaplasia = histologic reflexion of esophagus being exposed to stomach acid
89
Will all patients with GERD develop Barrett's esophagus?
No!
90
What can Barrett's esophagus develop into?
Adenocarcinoma of the esophagus
91
Will all patients with Barrett's esophagus develop esophageal cancer?
No! Risk = 1:3000 **amount of dysplasia present increases risk of cancer
92
What id dysplasia?
Abnormal development/maturation of cells Delay/abnormal differentiation of cells results in # of immature cells Indication of early neoplastic process
93
What are the regions of the stomach?
Cardiac = region where esophagus enters stomach Fundus = area above cardiac region Pyloric = area near duodenum Lesser and Greater curvature
94
What is the gastric function?
Digestion = secretion and some absorption Motility = propel food into duodenum
95
What is partially digested food called?
Chyme
96
How is food digested in the stomach?
Gastric juices
97
Which foods are absorbed in the stomach?
Aspirin NSAIDs Alcohol
98
What relaxes the stomach musculature?
Swallowing (prepares stomach for bolus)
99
What stimulates the motility of the stomach?
Vagus (cholinergic) Hormones: Gastrin and Motilin
100
Describe the sequence of gastric motility
Series of alternating small waves travel toward the pylorus 4 or 5 sequential peristaltic waves push chyme back and forth (churn) Last wave forces pyloric sphincter to open and chyme is pushed into duodenum (pylorus is open about 1 - 2 cm which is not enough to regurgitate back into stomach)
101
What is the average total time to empy the stomach?
50% after 2 - 3 hours Total emptying after 4 - 5 hours
102
What are the factors that increase rate of gastric emptying?
Larger food volume
103
What are the factors that decrease gastric emptying?
Hyper/hypotonic fluid Fatty Foods Increased rate of acids entering the duodenum
104
Why do you need decreased rate of gastric emptying when ingesting a hyper/hypotonic fluid?
Allow time to create/facilitate isoosmotic environment for the duodenum
105
When ingesting fatty foods what is the hormone that inhibits gastric motility and where is it released?
CCK (cholecystokinin) Synthesized/released by duodenum/SI **also decreases acid production)
106
Where are fats digested?
Duodenum
107
What happens if too much fat enters the small intestine?
Feedback loop slows down rate to allow time to properly digest fats
108
Where is acid neutralized?
Duodenum
109
What happens if too much acid enter the small intestine?
Feedback loop inhibits gastric emptying to decrease acid entering duodenum
110
What is pyloric stenosis also know as?
Infantile Hypertrophic Pyloric | Stenosis (IHPS)
111
What is going on with pyloric stenosis?
Muscles of pyloric sphincter are hypertrophied which impairs gastric emptying
112
How is pyloric stenosis treated?
Surgery = Pyloromyotomy
113
What is gastric juice?
Acid Mucous Pepsinogen
114
What are the major secretions of the stomach?
Mucus Acid Proteases Hormones Intrinsic Factor
115
What is the function of mucus?
Protect mucosal layer from acid and pepsin (protease) **stomach acid pH = 1.5
116
How does mucus protect the mucosal layer from stomach acid?
Provides transitional layer to protect the epithelium Contains high levels of bicarbonate (HCO3-) to neutralize the H+ --> pH of stomach = 1.5 and pH @ epithelial layer = 7
117
What are some stimuli of mucus secretion?
Prostaglandins (pathway = disrupted by NSAIDs) Nitric Oxide
118
What are some things that disrupt the mucus barrier?
Aspirin NSAIDs Alcohol Bile Salts (regurgitated from SI) Helicobacter pylori (bacteria)
119
What is the function of stomach acid?
Dissolve Food Inactivate bacteria/microorganisms that have been ingested Convert pepsinogen to pepsin
120
What cells secrete stomach acid?
Parietal cells in the body/fundus of the stomach
121
What molecule is "exchanged" for acid formation in the stomach?
Bicarbonate into the plasma **can lead to Alkaline Tide or Wave"
122
What stimulates acid secretion in the stomach?
ACh via vagus nerve (parasympathetic) Gastrin Histamine
123
What inhibits acid secretion in the stomach?
Gastrin inhibitory peptide (GIP) Somatostatin Secretin Prostaglandin
124
Where is somatostatin secreted from in the gastrointestinal tract?
Stomach Intestine Pancreas
125
What does secretin do?
Works synergistically w/ CCK to inhibit gastric motility
126
What cells produce and secrete pepsinogen?
Chief Cells
127
What does pepsinogen need to be converted to pepsin?
Acidic Environment (pH < 2)
128
What is the function of pepsin?
Proteolytic enzyme that breaks down proteins in the stomach
129
Where is pepsin inactivated?
Small Intestine (more alkaline environment)
130
What are the gastric hormones?
Gastrin Motilin Gastrin Inhibitory Emptying Peptide (GIP) Grehlin
131
What does gastrin do?
Promote gastric juice (acid) secretion and gastric motility
132
What cells secrete gastrin?
G Cells in stomach (located in antrum)
133
What does motilin do?
Promote stomach/SI motility
134
Where is motilin secreted?
From endocrine cells located in the small intestine
135
What does gastric inhibitory emptying peptide do?
Inhibit gastric juice (acid) secretion and gastric motility
136
Where is gastric inhibitory emptying peptide secreted?
Endocrine cells in the small intestine
137
What is Grehlin?
The "hunger hormone" Plays role in appetite sensation/feeding behavior **levels rise just before meals
138
Where is grehlin secreted?
Endocrine cells mostly located in the stomach Also from: kidneys, hypothalamus, pituitary, placenta
139
What is Intrinsic Factor?
Necessary for Vitamin B12 absorption in the small intestine
140
Where is intrinsic factor secreted?
Parietal Cells of the stomach
141
What are the epithelial folds of the stomach called?
Rugae
142
What are the cell types that are found at the surface of the folds of rugae?
Mucous Cells
143
What do the mucous cells in the rugae do?
Produce thick mucous = protection from abrasion of food and from pH levels in stomach
144
What cells are found at the base of the folds of rugae?
Gastric Glands (vary by stomach region)
145
Which cell type is found in the gastric glands in the body/fundus region of the stomach?
Mucous cells --> located @ neck of gastric glands Parietal Cells Chief Cells Enterochromaffin-like Cells
146
What do mucous cells do in the gastric glands @ the body/fundus of the stomach?
Secrete thin, watery mucus to liquefy stomach contents
147
What do parietal cells do in the gastric glands @ the body/fundus of the stomach?
Secrete acid (HCl) Secrete intrinsic factor
148
What do chief cells do in the gastric glands @ the body/fundus of the stomach?
Secrete pepsinogen (promote protein digestion)
149
What do enterochromaffin-like cells do in the gastric glands @ the body/fundus of the stomach?
Secrete histamine (promote acid secretion)
150
Which cells are found in the gastric glands in the cardiac region of the stomach and what do they do?
Mucous Cells --> secrete thin, watery mucus to liquefy stomach contents
151
Which cells are found in the gastric glands in the pyloric (antrum) region of the stomach?
Mucous Cells G cells
152
What do mucous cells do in the do in the gastric glands @ the pyloric region of the stomach?
Secrete thin, watery mucous to liquefy stomach contents
153
What do G cells do do in the gastric glands @ the pyloric region of the stomach?
Secrete gastrin (promote acid secretion/motility)
154
What are the 3 types of weight loss procedures?
Adjustable gastric band (LAP Band) Ventrical Banded Gastroplasty (VBG) --> stomach stapling w/ lap band" Gastric Bypass
155
Describe the adjustable gastric band procedure
Placement of band creates small pouch @ top of stomach Small pouch "fills" w/ food quickly and passage of food from top to bottom of stomach is slowed Upper part of stomach experiences sensation of fullness
156
Describe the Vertical Banded Gastroplasty (VBG)
Both band and staples are used to create a small stomach pouch Small opening in bottom of pouch through which food can pass through to rest of the stomach **smaller pouch helps person eat smaller portions and lose weight over time
157
What are the initial outcomes seen with VBG?
Vary from: "complete" weight loss some weight loss poor weight loss
158
What are the longterm outcomes seen with VBG?
Many patients will regain weight by gradually stretching small pouch
159
Describe gastric bypass procedures
Physically redirects anatomy of GI tract --> bypass created so chyme bypasses proximal small intestine Point is to limit absorption of calories (and nutrients) in small intestine
160
What are the outcomes of gastric bypass?
Long/short term outcomes suggested to be better than banding/stapling procedures
161
What is the most common restrictive operation for weight control?
Vertical Banded Gastroplasty (VBG)
162
What are the complications of gastric bypass?
Nutritional deficiencies --> need long term supplementation plan Dumping syndrome --> rapid gastric emptying Direct complications to GI tract --> bleeding, infections, etc
163
What exactly is dumping syndrome?
Jejunum rapidly fills w/ undigested food from stomach?
164
What are the signs/symptoms of dumping syndrome?
Cramping Bloating Nausea Vomitting Diarrhea Shortness of Breath
165
What is gastritis?
Inflammation (diffuse through lining) of gastric mucosa)
166
When would you see acute gastritis?
W/ injury to the gastric mucosa
167
What are some causes of acute gastritis?
Drugs/Chemicals --> NSAIDs H. pylori infection Alcohol Smoking
168
How long will acute gastritis last?
A few days but want to remove offending facotr ASAP
169
What is chronic gastritis?
Degenerative gastritis --> Chronic inflammation, mucosal atrophy and epithelial metaplasia
170
When do you see chronic gastritis?
More common in elderly
171
What are the 2 types of chronic gastritis?
Type A = chronic fundal gastritis --> in fundus/body Type B = chronic antral gastritis
172
Which type of chronic gastritis is more common?
Type B = 4x more common than A
173
Which type of chronic gastritis is considered autoimmune dysfunction?
Type A --> antibodies attack parietal, chief cells and intrinsic factor
174
If Type A chronic gastritis is autoimmune, what is the problem with Type B?
Seems to be more of motiltiy problem; no loss of acid secretion, parietal cels, intrinsic factor
175
Where in the stomach do you see most gastric ulcers?
Antrum
176
What kind of feedback is involved w/ gastric uclers?
(+) feed back: Chronic exposure to various substances --> breakdown of protective mucosal lining of stomach Damaged mucosa releases histamine --> increased release of acids/pepsinogen, increased capillary permeability
177
Do gastric ulcers possess higher risk of cancer?
Yes (vs. risk for duodenal ulcer)
178
What are the 2 major risk factors for benign gastric ulcers?
Chronic use of aspirin, NSAIDs H pylori infection
179
What are the clinical signs and symptoms of a gastric ulcer?
Food provoking pain pattern --> pain immediately after eating

Patho Summer Test #1 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions