✅1.9 PHYSIOLOGY - GI Flashcards
(113 cards)
0
Q
Location of submucosal plexus
A
Between submucosa and inner circular muscle
1
Q
Basic GI layers
A
Mucosa
Submucosa
Muscularis
Serosa
2
Q
Other name for submucosal plexus
A
Meissner’s plexus
3
Q
Function of submucosal plexus is mainly for
A
Secretion
4
Q
Function of myenteric plexus
A
Motility
5
Q
Other name for the myenteric plexus
A
Auerbach’s plexus
6
Q
Location of the myenteric plexus
A
Between inner circular and outer longhitudinal muscle
7
Q
3 parts of the mucosa
A
Epithelium
Lamina propria
Muscularis mucosa
8
Q
Innervation of the muscularis mucosa (mucosa)
A
Meissner’s plexus
9
Q
Brunner’s glands vs peyer’s patches
Function, location (gross and layer)
A
Brunner’s - duodenum, HCO3 secretion, submucosa
Peyer’s patches - ileum, IgA secretion, lamina propria
10
Q
Which layer is not seen in the esophagus?
A
Serosa
11
Q
Strongest layer of the esophagus
A
Submucosa
12
Q
Bolus vs chyme vs feces
A
Bolus - esophagus and stomach
Chyme- mixed with HCl, SI
Feces - nutrients absorbed, found in the LI
13
Q
Function of CCK
A
Bile secretion and inhibition of gastric emptying
14
Q
3 incretins
A
Glucagon
GLP-1
GIP
15
Q
Number one trigger of CCK secretion
A
Fatty acids
16
Q
CCK is secreted by what cells in the _____
A
I cells
Duodenum and jejunum
17
Q
Motilin does not have effects on the
A
Large intestine
18
Q
Stimulus for motilin
A
Fasting
19
Q
“Janitor” GI hormone
A
Motilin
20
Q
Motilin is from what cells in the ______
A
M cells
Duodenum and jejunum
21
Q
Function of motilin
A
Interdigestive/migrating myoelectric complex
22
Q
GIP is produced from what cells in the _____
A
K cells , duodenum
23
Q
Function of GIP
A
Increases insulin secretion
24
3 parts of the mucosa
Epithelium
Lamina propria
Muscularis mucosa
25
2 muscles in the muscularis layer
Inner circular
| Outer longhitudinal
26
Other name for serosa
Adventitia or mesothelium
27
Muscular layers in the stomach
Inner oblique
Middle circular
Outer longhitudinal
28
The myenteric plexus is mainly excitatory except for which regions
Pyloric sphincter and ileocecal valve
29
Cell source of CCK
I cells duodenum
30
Cell sources of GIP and GLP-1
GIP- k cells
| GLP-1 L cells
31
Main stimulus for CCK
Fatty acids
32
Main stimulus for incretins
Oral glucose
33
Effect of motilkn
Stimulates interdigestive myoelectric complexes
34
Stimulus for motilin
Fasting
35
Effect of CCK
Inc bile
GB contraction
Inhibits gastric emptying time
36
Most potent stimuli for gastrin secretion
Phenylalanine
Tryptophan
Methionine
37
Neurocrine from vagus nerve to G crlls
GRP / Bombesin
38
GI hormones classified as incretins
GLP-1
| GIP
39
Candidate GI hormones
Pancreatic polypeptide
Enteroglucagon
GLP-1
40
Function of enteroglucagon
Secreted by intestinal cells in response to hypoglycemia
41
GI paracrines
Somatostatin
| Histamine
42
Mnemonic for function of somatostatin
Somato STOP IT
inhibits release of all GI hormones
43
Histamine is secreted by
Mast cells of GI mucosa
44
Function of ACH and norepi in sphincters
ACH relaxes sphincters while Norepi contracts sphincterd
45
Inhibits appetite and is found in the ventromedial nucleus
Satiety center
46
Stimulates appetite and is found at the lateral hypothalamic area
Appetite/hunger center
47
Sends signals to satiety and hunger centers
Arcuate nucleus
48
Releases POMC to decrease appetite
Anorexigenic neurons
49
Releases neuropeptide y to increase appetite
Orexigenic neurons
50
Stimulates anorexigenic neurons and inhibits orexigenic neurons
Leptin, insulin, GLP-1
51
Inhibits anorexigenic neurons
Ghrelin
52
Inhibits ghrelin
Peptide YY
53
Mnemonic for satiety and hunger centers
Ventromedial
VUCHOG
Satiety center
Lateral hypothalamic area
LAMON
Hunger center
54
2 types of GI smooth muscle contractions. Differentiate
Tonic - slow - false action potentials
Phasic- spike pptentials - true potentials
55
Slow waves are generated by the GI pacemaker called
Intertstitial cells of cajal
56
Slowest slow wave frequency is found in the
Stomach
57
Fastest slow wave frequency is found in the
Small intestines
58
Type of GI contraction for mixing and propulsion
Phasic contractions
59
Most common stimulus for GI peristalsis
Distention
60
What is the myenteric reflex?
Muscles upstream contract, muscles downstream exhibit receptive relaxation
61
What is the law of the GUT?
Myenteric reflex +anal direction of peristalsis
62
How long does it take to transfer material from pylorus to ileocecal valve?
From ilececal valve to colon?
3-5 hrs
8-15 hrs
63
Chewing is always voluntary. T or F.
It may be involuntary
64
Other name for amylase
Ptayalin
65
Phases of swallowing
Oral
Pharyngeal
Esophageal
66
Swallowing center
Medulla
67
Esophageal peristaltic contraction
2 phases - primary and secondary
Primary peristalsis propels the food to the stomach while secondary persistalsis is for clearance of remaining food.
68
Receptive relaxation of the orad stomach is mediated by
VIP
Relax pag may VIP
69
Capacity of the stomach
1.5 L
70
____ increases distensibility of orad stomach
CCK
71
Caudad stomach contracts ___x per minute
3-5x
72
Back and forth movement of the SI with no net forward motion for mixing chyme with enzymes
Segmentation contraction
73
Sac like segments due to the segmental contractions in the large intestine
Haustra
74
Function of proximal vs distal colon
Proximal - absorption of water
| Distal - storage of feces
75
Urge to defecate is felt once rectum is ___%filled
25%
76
Definition of valsalva maneuver
Expiration on a closed glottis
77
Odor in stool is due to bacteria producing
Indole
Skatole
Mercaptan
Hydrogen sulfide
78
Incomplete vomiting / closed UES
Retching
79
Vomiting is a wave of reverse peristalsis that begins from the
Small intestine
80
GI organ with the most volume of secretion
Small intestines
| 1800ml
81
Only essential secretion of the stomach
Intrinsic factor
82
Other name for parietal cells
Oxyntic cells
83
Other name for chief cells
Peptic cells
84
Secretes serotonin
Mnemonic
Entrochromaffine cells
Ser pls ENTER
85
Secretes histamine
Enterochromaffin LIKE cells
86
3 substances that stimulate HCL secretion and corresponding receptord
Histamine - H2
Ach -M3
Gastrin -CCK-B
87
Inhibitors of HCL secretion
Low pH (
88
Phases of HCL secretion
Cephalic
Gastric
Intestinal
89
Most common component of bile
Water
90
Active component of bile
Bile salts
91
Primary bile acids
Cholic acid
| Chenodeoxycholic acid
92
Secondary bile salts
Deoxycholic acid
| Lithocolic acid
93
Bile salts from deoxycholic acid
Glycodeoxycholic acid
| Taurodeocycholic acid
94
Bile salts from lithocolic acid
Glycolithocolic acid
| Taurolithocolic acid
95
Bile salts are utilized ____x before excreted in the feces
17x
96
How do you absorb glucose and galactose from lumen to intestine
SGLT-1
97
How do you absorb fructose from lumen to intestine
GLUT 5
Mnemonic: 5 letters
FRUIT and LUMEN
98
How do you absorb glucose, galactose and fructose from intestinal cell to the blood?
GLut 2
Two letters
BM - basement membrane
99
Is pepsin essential for protein digestion?
No. Trypsin ("aka nuclear bomb") is the essential one for digestion
100
What is the optimum pH for pancreatic lipase activity?
6.0
101
Bile salts inactivate pancreatic lipase. What coenzyme is secreted to prevent this from happening?
Prolipase---> colipase
102
Only product of TGL metabolism that is not hydrophobic
Glycerol
103
What type of fatty acids go directly to the portal vein instead of lacteals?
Short and medium chain FA
104
Main site for water absorption
Jejunum
105
Primary ion secreted in the intestinal lumen
Cl
106
Needed to absorb calcium
Cholecalciferol
| 1,25 OH2
107
Needed to absorb iron
Vitamin C
108
Part of the metabolism of these vitamins involve the colonic flora
Vit K, B1, B2, B12
109
Liver models
Classic liver lobule
| Liver acinus model
110
Zones of the liver acinus model
Zone 1 periportal
2 midzonal
3 centrilobular
111
Special liver cells for vitamin storage
Ito cells
| Space of disse
112
Liver macrophages
Kuppfer cells
| Liver sinusoids
