Gastro Flashcards
1
Q
What type of diarrhea is associated with lactose-intolerance and malabsorption?
A
osmotic type of diarrhea
2
Q
What are the layers of the alimentary canal from deep to superficial?
A
Mucosa
Submucosa
Muscular externa
serosa
3
Q
What is the mucosa composed of?
A
Mostly epithelium and some CT, surrounded by a thin layer of smooth muscle
4
Q
Which layer has blood vessels, lymph nodes, lymph vessels and nerve endings?
A
Submucosa
5
Q
In what part of the mucosa are digestive enzymes secreted?
A
Mucosal epithelium
6
Q
What secretes mucus for lubrication?
A
Goblet cells
7
Q
T/F: the submucosa is composed of two layers of connective tissue
A
False submucosa if composed of soft CT
8
Q
What are Peyer patches? What are they similar to?
A
Lymph nodes similar to tonsils
9
Q
What are two layers that compose the muscular externa?
A
Inner and outer layers of smooth muscle
10
Q
Describe the orientation of the inner and outer layers of the musclular extern. how do they run?
A
Inner layer – encircles the canal
outer layer – longitudinal and lies in the direction of the canal
11
Q
Which muscles surrounds the stomach?
A
Inner layer – encircles the canal
outer layer – longitudinal
Third layer of oblique smooth muscle
12
Q
Why is there a 3rd layer of muscle in the stomach?
A
Stomach needs to mix the food
13
Q
What is syncytium?
A
To function as a coordinated unit
14
Q
What is the serosa part of in the alimentary canal?
A
Visceral peritoneum
15
Q
What is the serosa composed of?
A
Connection tissue covered with squamous epithelial cells
16
Q
Name the functions of serious fluid
A
Keep alimentary canal moist
Allows for friction free movement of the intestine
17
Q
What is found between each of the four layers of the G.I. tract?
A
Network of nerves
18
Q
The serosa layer of the G.I. tract is connected to what?
A
Mesentery
19
Q
What comprises enteric plexus?
A
Myenteric and submucosal plexus
20
Q
What type of controls are there on the gut?
A
Sympathetic
Parasympathetic
Spinal Cord
Brain Stem (Reflexive)
21
Q
Which nerve plexi is responsible for Movement?
A
Myenteric plexus
22
Q
What is SuBmucosal plexus responsible for controlling?
A
G.I. secretions and local blood flow
23
Q
What are the cranial nerves associated with innervation of the gut?
A
Vagus nerve
Glossopharyngeal nerve
24
Q
What are the two plexi in the GI that regulate GI controls?
A
Submucosal plexus
Myenteric plexus
25
List the digestive process (7) – I poop more crap and secrete shit
```
Ingestion
Propulsion mechanical digestion
chemical digestion
Absorption
Secretion
Storage and elimination
```
26
T/F: absorption is the passage from the GI tract to the blood/lymph vessels and could be active or passive
T
27
T/F: secretion is the elimination out of the GI tract
false secretion is the elimination into the GI tract (lumen)
28
What general structures are involved in digestion?
alimentary canal and accessory structures
29
Where does mechanical digestion occur? And what is that process called in each location?
Mouth – chewing
Stomach – churring
Small Intestines – segmentation
30
What are the two components of propulsion?
Swallowing and peristalsis
31
What organs are involved in peristalsis?
Esophagus, stomach, small intestine, large intestines
32
What is mainly absorbed from the sigmoid colon?
Water
33
What is ECL what is it secreted?
"entero chromafin like cells" - type of neuroendocrine cell that synthesize and secrete histamine in the stomach
34
What does GIP stand for?
– gastric inhibitory peptide
35
Other than mucus, what is secreted into the small intestine?
Hormones: CCK, secretin, GIP, and other
36
Does any digestion occur in the large intestine?
None except for bacteria
37
What does the oral cavity and esophagus digest?
Carbohydrates and some fats
38
What is secreted in the oral cavity and esophagus?
Saliva
| lipase
39
Where does absorption begin in the alimentary canal? And what is absorbed there?
The stomach and lipid soluble substances are absorbed (aspirin or alcohol)
40
What happens during peristalsis?
Leading wave of relaxation due to: the gut senses stretch muscle before distention to constrict post area relaxes
41
What is segmentation? what happens to the bolus?
Mixing and churning
| Shearing forces cause the bollus to split in half
42
What is found in saliva?
Carbohydrate Digestion – Amylase
| Has Immunoglobulins
43
What stimulates saliva secretions?
Parasympathetic and beta adrenergic
44
What are the salivary glands?
Parotid gland
Submandibular gland
Sublingual gland
45
Explain what happens during swallowing (be specific)
Bollus is pressed up your palate and you upper esophageal spincter is contracted
The sphincter then relaxes to allow food to pass and contracts again to prevent it from coming back up
46
What are the two sphincters in the esophagus?
UES
| LES
47
What sphincter is located at the entrance of the stomach and prevents acid reflux?
LES aka cardiac
48
What do circular muscles do during deglutition? What happens to the bolus?
Circular muscles contract above the bolus pushing the bolus down
49
What do longitudinal muscles do during deglutition? What happens to the bolus?
Contract which shortens the passageway ahead for the bolus
50
Name the 4 roles of the stomach
```
MACE
Mechanical digestion
absorptions
Chemical digestion
Enteroendocrine function
```
51
What chemicals are involved in chemical digestion in the stomach?
Pepsin
| Hydrochloric acid
52
What are the 3 muscular layers of the stomach?
Outer - longitudinal layer
Inner - circular layer
3rd layer - oblique layer (body)
53
What are the secretory stomach cells?
Mucus neck cells
Parietal cells
Chief cells
Enteroendocrine cells
54
What are the gastric hormones?
Gastrin
| Somatostatin
55
What do parietal cells secrete?
HCl and intrinsic factor
56
What is intrinsic factor important for?
Absorption of B12
57
What releases pepsinogen?
Chief cells
58
Which hormone inhibits stomach secretory activity and gastric emptying?
Somatostatin
59
Which gastric hormone is secreted by the stomach and duodenum?
Somatostatin
60
What hormone is responsible for stimulating secretory activity, gastric emptying and contractions of the intestines?
gastrin
61
What are the three phases of Gastro secretion?
Cephalic phase
Gastric phase
intestinal phase
62
T/F: during the cephalic phase though taste smell or tactile sensation of food causes a parasympathetic neurons (vagus) to stimulate secretion of hydrochloric acid and pepsin in the stomach and gastrin in the lower stomach to the blood steam stimulating pepsin and hcl secretion to upper stomach
T
63
T/F: during gastric phase distention causes the vagus nerve to send signals to medulla oblongata and causes more pepsin and hcl to be secreted
T
64
T/F: during the intestinal phase chyme enters the duodenum and secretion stops when it contains enough lipids or the ph has reached 3.5
T
65
List the 3 responses to decrease gastic secretion
Medulla oblongata inhibits secretions
Bloodstream via hormones
Local reflex inhibits secretions
66
What hormones are secreted in the Duodenum?
Secretin
| Cholecystokinin (CCK)
67
What stimulates secretin?
Acidic chyme
68
What is secretin stimulated by and what does it inhibit/stimulates?
Stimulated by acidic chyme
Inhibits gastric gland secretions and gastric motility
Increases output of pancreatic juices and bile (partietal chief relax)
69
What does Cholecystokinin (CCK) increase/stimulate?
Increases production of pancreatic juices
| Stimulates gallbladder to expel bile
70
What does bile do?
Emulsifies fat, product is bilirubin
71
What does bile contain?
```
BPCF
Bile salts
Pigments
Cholesterol
fats
```
72
How much bile is produced in just one day?
700-1200 bile/day
73
What does the enterohepatic circulation recycle?
Bile salts
74
What are the functions of the liver?
```
MR VIDS
Metabolizes nutrients and bilirubin
Metabolic detoxification
Stores minerals and vitamins
Vascular and hematologic functions
Recycles bile salts
Some cells play a role in the immune system
```
75
Describe how the blood travels through the liver
From the portal vein up the portal venules across sinusoids to central vein through interlobular to hepatic vein Vena Cava now full of nutrients
76
What does the portal triad consist of?
Bile duct
Portal arteriole
Portal venule
77
When are bacteria most likely to migrate out of the gut? What can this cause?
Ulcer and causes septis or endocarditis
78
what cells associated with liver function remove bacteria?
Reticulo endothelial cells
79
What are the mechanisms that promote the secretion of bile?
1. Acidic / fatty chyme entering duodenum causes release of cholecystikinin and secretin from DUODENAL WALL ENTEROENDOCRINE CELLS
2. these hormones enter the bloodstream
3. Bile slats abd secretin transported via bloodstream stimulate liver to produce bile more rapidly
4. vagal stimulation causes weak contractions of gallbladder
5. Cholecystokinin (blodstream) causes gallbladder to contract and hepatopancreatic sphincter to relax = bile enters duodenum
6. Bile salts reabsorbed
80
How does nutrients absorbed in the small intestines get back into systemic circulation?
Blood flow from the intestines goes from the intestines through the liver then into the IVC
81
What is secreted by pancreas?
Pancreatic juices PAL = Pancreatic protease amylase and lipase
And bicarb
82
What are the mechanisms that promote the secretion of pancreatic jucies?
1. Acidic chyme entering duodenum causes enteroendocrine cells to release secretin and fatty protein rich chyme induces release of cholecystikinin
2. these hormones enter the bloodstream
3. Cholecystokinin induces release of pancreatic juices upon reaching the duodenum
Secretin causes copious secretion of bicarb rich pancreatic juice
83
What does CCK do?
Secretion of enzymes of pancreas
| Gallbladder contract hepatopancreatic spintcher to contract
84
What are the major roles of the small intestines?
Majority of water and salt absorption
Majority of nutrient absorption
segmentation mixes
85
What increases the surface area in the small intestines?
Large circular folds are covered with Microvilli which contain a counter current system of capillaries
86
What is the function of intestinal flora?
| Prevents growth of opportunistic organisms
```
It metabolizes:
bile salts
drugs
nitrogenous substances,
vitmain synthesis (e coli)
```
87
Name some intestinal flora?
E coli clostridum cloriform
88
How much do intestinal flora comprise distal to ileocecal valve?
1/3 of bulk of feces
89
What is the role of the large intestine?
absorbs vitamins
absorbs water
stores and moves fecal material
90
Whats involved in the digestion of carbs?
Salivary amylase and pancreatic amylase in the mouth and the small intest
Carbs converted to polsac then monosac by brush border enzymes in small intestine
-monosac in vili go to liver
91
Whats involved in protein digestion? Absorbed?
Protein is broken down in the stomach by pepsin, when HCl is present.
The large poly pep are further broken down by pancreatic enzymes to small poly pep
Brush border enzymes break the small poly peps to amino acids
-Enter the capillary blood in the villi transported to liver via hepatic portal vein
92
How are unemulsidied fats absorbed?
They are emulsified by the detergent action of bile salts and the pancreatic lipase (both in small intestine)
Monoglycerides and fatty acidenter intestinal cells via diffusion combine with… lymph ducts
Glycerol and fatty acid capillary blood villi lacteal(middle of countercurrent) to to liver
They are emulsified by the detergent action of bile salts and the pancreatic lipase (both in small intestine)
Monoglycerides and fatty acid enter intestinal cells via diffusion combine with… lymph ducts
Glycerol and fatty acid capillary blood villi lacteal(middle of countercurrent) to to liver
93
What is the emuslsification of fat?
Breakdown of large fat globlet into smaller droplets
94
how does Bile acts as an emulsifying agent in the digestive tract?
Its nonpolar region binds to fat dispersing ingested fats into small globules
95
When does Lipogenesis occur?
Too much glucose
96
Glycogenesis vs gluconeogenesis
Glucose to glycogen
| Aminoacid to glucose
97
What is the breakdown biproduct of protein? How is the biproduct excreted?
ammonia --> urea --> urine
98
What do carbs and lipids become?
Structural components of cells
Specialized derivative (steriod)
Energy
Storage
99
What do amino acids become?
components of proteins
| nitrogen containing derivative (hormones NT)
100
what gets absorbed in the stomach, duodenum, jejunum, ileum, and colon?
```
Stomach s.AW
Duodenum icfsw pmsv
Jejunum J.PS
Ileum I.BBC
Colon C.EW
```
101
Define anorexia
Lack of appetitie dispite stimuli that would normally producer hunger
102
What are common sx associated with nausea?
Hypersalivation and tachycardia
103
What is nonproductive vomiting?
Retching
104
Define projectile vomiting
Spontaneous vomiting that doesn’t floowing nausea or retching
105
What are the causes of constipation?
```
Neurogenic disorders,
functional or mechanical conditions,
low-residue diet,
sedentary lifestyle,
excessive use of antacids
```
106
What are the different mechanisms of diarrhea?
Osmotic
Secretory
Motility
107
T/F: diarrhea is the increase frequency of BM, increased volume fluidity and DECREASE in weight of the feces
f- increase
108
What does diarrhea cause?
Weight loss
electrolyte imblance
metablolic acidosis
dehydration
109
GI manifestations of actute Bacterial infection or viral infection
fever, w/ or w/o cramps
110
IBS cause…?
Fever cramping bloody stool
111
Streatorrhea is a sign of what?
Malabsorption
112
What are types of ab pain?
Patiental
Visceral
Reffered
113
What are the Biochemical mediators of the inflammatory response that stimulate organic nerve endings producing abdominal pain?
histamine, bradykinin, and serotonin
114
Upper GI bleed comes from
SED
115
Lower GI comes from
jeju ilium colon rectum
116
What would cause an upper GI bleed?
Varcies (varicose around esophagus – increases pressure)
ulcer,
mallory –weiss (tear from vomiting)
117
What can cause lower gi bleed?
Polyps
IBS
Cancer
Hemorroids
118
How can you tell a pt is going into shock from a GI bleed?
With loss of 1000 ml or more, or 20-25% of blood volume loss within a few hrs
Herat Rate is greater than 100 BPM
Systolic BP is less than 100 mm Hg
119
test for GI bleed
BMX CLUE
Barium Enema
MRI/CT
X-Rays – flat and upright
Cholecystogram – oral contrast
Liver Enzymes/Bilirubin/Serum Proteins
Ultrasound
Endoscopy – ERCP, Colonocopy
120
What are disorder of motility?
```
Dysphagia
Achalasia
GERD
Hiatal hernia
Intestinal obstruction and ileus
```
121
What are the types of dysphagia?
Mechanical or functional obstruction
122
What is achalasia?
Denervation of smooth muscle in the esophagus and lower esophageal sphincter relaxation
123
Whats the differnecce btwn gerd and reflux esophagitis?
Its called relux esophagitis when GERD causes inflammation
124
What must a normal functioning LES maintain to prevent reflux?
a zone of high pressure to prevent chyme reflux
125
What can contribute to GERD?
Condition that increase abdominal pressure
126
What can continous GERD cause?
Barrett Esophagus – premalignant change
127
List the manifestations of GERD (3)
Heartburn, regurgitation of chyme, and upper abdominal pain within 1 hour of eating
128
What are the two types of hiatal hernia? Which one is better?
Sliding hiatal hernia*
| Paraesophageal hiatal hernia
129
What is an obstruction of the intestines called?
Ileus
130
What is an ileus?
Any condition that prevents the flow of chyme through intestinal lumen OR failure of normal intestinal motility w/o an obstructing lesion
131
Intestinal obstrruction presents with what manifestations?
```
Colicky (comand an go) pain
vomiting
Distention
Hypovolemia
Metabolic acidosis
```
132
How are GI obstructions characterized?
Acute or chronic
Partial or complete
Simple or strangulated
Functional or mechanical
133
what are the causes of mechanical obstruction?
Volvulus = twist
Adhesion
Incarderation = strangulated
Intusssception = folding inward
134
What layer does gastritis affect?
Mucosa
135
Causes of gastritis?
h.Pylori and NSAIDS
136
What are two types of gastritis?
Acute and chronic
137
What is PUD?
A break or ulceration in the protective mucosal lining of the lower esophagus, stomach, or duodenum
138
What is the difference between superficial PUD ulcers and deep?
Superficial – slight Erosions
| Deep - True ulcers
139
Whats the most common type of peptic ulcer?
Duodenal
140
What are the developmental factors of duodenal ulcers?
Hypersecretion of stomach acid and pepsin
| Use of NSAIDs
141
Where does gastric ulcers tend to develop?
antral region of the stomach
142
What is the primary change in gstric ulcers?
increased mucosal permeability to hydrogen ions
| Gastric secretion is normal of less than normal
143
Whats the most common type of peptic ulcer?
Duodenal
144
What are the developmental factors of duodenal ulcers?
Hypersecretion of stomach acid and pepsin
Use of NSAIDs
High gastrin levels
Acid production by cigarette smoking
145
How does h pylori create ulcers?
Toxins and enzymes that promote inflammation and ulceration
