Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

GI Physiology > Exam 2 (Neuroendocrine + Oral Digestion) > Flashcards

Exam 2 (Neuroendocrine + Oral Digestion) Flashcards

1
Q

Two types of clinically relevant enteric interneurons

A

serotonergic
enkephalinergic

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

What do serotonergic interneurons facilitate?

A

effector neuron action

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

Serotonergic NT

A

serotonin

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

What 2 responses occur with serotonergic interneurons?

A
  1. increase peristalsis
  2. increase net fluid secretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What diseases can occur involving serotonergic interneurons?

A
  1. carcinoid syndrome
  2. inflammatory diarrhea (salmonella)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Carcinoid syndrome is a ______ tumor that secretes _____.

A

neuroendocrine
serotonin

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

Salmonella is an inflammatory diarrheal disease that increases _____ secretion.

A

serotonin

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

Enkephalinergic interneurons overall function

A

establish “segmentation” pattern

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

What is the lay term equivalent to enkephalinergic neurons?

A

“gut endorphins”

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

What 2 responses occur from Enkephalingeric neurons?

A

-inhibit effector neurons of alternating segments (= promote mixing contents)
-decrease secretion & increase absorption

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

What are the overall 3 functions of enkephalingeric interneurons?

A
  1. slow aboral transit
  2. enable mixing
  3. increase net fluid absorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is Loperamide? What’s another name for it?

A

synthetic opiate (type of enkephalinergic interneuron)
imodium

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

Functions of Loperamide

A

mimics enkephalin
anti-diarrheal

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

____ NS is local while ____ is outside gut wall.

A

enteric
extrinsic

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

Which type of innervation has the dominant tone of the alimentary tract?

A

PSNS

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

Main function of PSNS innervation of extrinsic NS

A

promote digestion
coordinate enteric NS

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

3 responses to PSNS activity in extrinsic NS

A
  1. motility patterns (peristalsis)
  2. net fluid secretion
  3. vasodilation splanchnic vasculature (up blood flow to GI)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

PSNS innervation = same as ______ of Enteric NS because ENS plexis = ______ neurons of PSNS

A

effector neurons
postganglionic

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

When does the SNS of the Extrinsic NS have dominant tone on alimentary tract?

A

fight or flight
or
in long reflex

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

Main function of SNS innervation of Extrinsic NS

A

inhibit digestion
recover fluid volume

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

What 3 responses occur due to the SNS of the Extrinsic NS?

A
  1. decreased motility (conserve E)
  2. increase net fluid absorption
  3. vasoconstriction of splanchnic vasc.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

(SNS/PSNS) increases blood flow to GI tract while (SNS/PSNS) increases circulating blood volume.

A

PSNS
SNS

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

Cholinergic innervation of striated muscle occurs what two locations?

A

esophagus
external anal sphincter

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

PSNS is made up of what 2 neuron types?

A

PSNS preganglionic neurons
PSNS postganglionic neurons (interneurons + effector of enteric NS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

SNS makes up what neuron types/pathway?

A

CNS –> preganglionic neurons –> external ganglia –> postganglionic neurons –> gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

If the gut wall was cut off from the CNS, what NS would be intact? Which would be lost?

A

enteric NS intact
SNS lost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What responses would be seen if CNS cut off from gut wall?

A

up peristalsis
up secretion
up vasodilation
dominant PSNS control, no SNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Long reflexes are part of the ____ nervous system.

A

extrinsic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the function of long reflexes?

A

regulate digesta over long intestine distances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the two main types of long reflexes?

A

stimulatory
inhibitory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is one type of stimulatory long reflex? What organ is acted on?

A

gastrocolic (stomach –> colon)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the 4 types of inhibitory long reflexes? What organs are acted on?

A
  • enterogastric (SI –> stomach)
  • enteroenteric (SI –> SI)
  • coloileal (colon –> terminal part SI)
  • ileogastric (ileum –> stomach)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Stimulus of Gastrocolic Reflex

A

full stomach (stretch)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Response of Gastrocolic Reflex

A

increase colon motility = move content to rectum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What neuron type is present in all long reflexes?

A

GVA (general visceral afferent) –> send info to CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Outcome of Gastrocolic Reflex (PSNS/SNS)

A

up PSNS
down SNS to colon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Stimulatory Long Reflexes overall function

A

speed transmit of GI contents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Inhibitory Long Reflexes overall function

A

slow transit of Gi contents to avoid overfilling of a segment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Enterogastric reflex stimulus

A

digesta in upper SI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Enterogastric reflex response

A

inhibit gastric emptying (decrease GI motility)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Output of Enterogastric Reflex (PSNS/SNS)

A

down PSNS | up SNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Stimulus of Enteroenteric Reflex

A

digesta in SI (distal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Enteroenteric Reflex response

A

inhibit peristalsis of intestine (distal SI inhibits site oral to it to prevent overfilling)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Enteroenteric Reflex response (PSNS/SNS)

A

down PSNS
up SNS @ oral site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Coloileal reflex stimulus

A

full colon (stretch)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Coloileal reflex response

A

inhibit ileal emptying (decrease motility)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Coloileal reflex Output (PSNS/SNS)

A

down PSNS
up SNS @ ileum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Ileogastric Reflex Stimulus

A

full ileum (stretch)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Ileogastric reflex response

A

inhibit gastric emptying

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Ileogastric reflex (PSNS/SNS)

A

down PSNS
up SNS @ stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What are the 4 different modes of action of GI hormones?

A
  1. endocrine
  2. paracrine
  3. neurocrine
  4. exocrine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Which mode of action for GI hormones are hormones secreted by nerve cell –> target cell (similar to NTs)?

A

neurocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Which mode of action for GI hormones use local diffusion –> target?

A

paracrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Which mode of action for GI hormones enters the bloodstream directly –> target?

A

endocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Which mode of action for GI hormones enter the lumen –> target?

A

exocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What are the 3 main hormone families (GI peptide hormones for GI function)? By what similarities are they grouped?

A
  1. Gastrin/Cholecystokinin (CCK)
  2. Secretin
  3. Other

Grouped by amino acid composition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What are the 2 neural stimuli for gastrin?

A
  1. acetylcholine (vagus N)
  2. GRP (gastrin-releasing peptide)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What are the 2 luminal stimuli for gastrin?

A

amino acids (in gastric lumen)
gastric pH > 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Location of Gastrin

A

antrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Cell type that releases Gastrin

A

G cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Mode of Action (Gastrin)

A

endocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Target organ for Gastrin

A

glandular stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Response to Gastrin

A

parietal cells: HCl secretion
chief cells: pepsinogen release
up GI motility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Another name for CCK

A

pancreozymin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Luminal stimuli for CCK

A

amino acids (upper SI)
fats (upper SI)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

CCK Location

A

upper SI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Cell type than releases CCK

A

I cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Mode of action for CCK

A

endocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Target organs & their responses to CCK (3)

A
  1. pancreatic acini –> secrete pancreatic proenzymes
  2. gallbladder –> contracts GB
  3. sphincter of oddi –> relaxation (bile release)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Secretin stimulus for release

A

H+ ions (upper SI)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Secretin Location

A

upper SI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What cell type releases Secretin?

A

S cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Mode of Action for Secretin

A

endocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Target for Secretin

A

pancreatic duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Response to Secretin

A

stimulate HCO3-rich + watery secretion (hydrolatic)

76
Q

What is the name for the secretion subgroup that contains 3 different GI peptide hormones?

77
Q

What 3 peptide hormones are within the incretin subgroup?

A
  1. GLP-1 / GLP-2 (glucagon-like peptides)
  2. GIP (glucose-dependent insulinotropic peptide)
  3. VIP (vasoactive intestinal peptide)
78
Q

GLP-1 / GLP-2 Stimuli

A

carbohydrates (in SI)
hyperosmolar solution (SI)

79
Q

Location of GLP-1/2

A

small intestine

80
Q

Cell type that releases GLP

81
Q

Mode of Action of GLP-1/2

82
Q

Targets/Responses (3) of GLP-1/2

A

pancreatic B cells –> up insulin secretion
stomach –> inhibit GI motility
intestine –> mucosal growth

83
Q

Which response of GLP-1/2 is via the CNS and therefore neuroendocrine?

A

inhibition of GI motility in the stomach

84
Q

GIP stimulus

A

carbohydrates (in SI)

85
Q

Location of GIP

A

small intestine

86
Q

What cell type release GIP?

87
Q

Mode of Action for GIP

88
Q

Target/Response of GIP

A

pancreatic B cells –> up insulin secretion

89
Q

What GI peptide is part of the secretin family and is a neurotransmitter similar to secretin (neurocrine)?

A

VIP (vasoactive intestinal peptide)

90
Q

Secretin release is coupled with ____ release which stimulates what?

A

CCK
release of pancreatic proenzymes
= complimentary actions of hormones

91
Q

What 4 GI peptides are in the “other” family?

A
  1. somatostatin
  2. histamine
  3. motilin
  4. guanylin
92
Q

What is the stimulus for Somatostatin release?

A

H+ ions (stomach pH < 4)

93
Q

Location of Somatostatin

94
Q

Cell type that produces somatostatin

95
Q

Mode of action for Somatostatin

96
Q

Target for Somatostatin

97
Q

What two cells produce responses from Somatostatin? What is their response?

A

parietal cells + chief cells
inhibit gastric acid & pepsin secretion

98
Q

What other two responses (other than from parietal & chief cells) occur from Somatostatin?

A

release gastrin (at G cells)
release histamine (ECL)

99
Q

Overall, what is the response to Somatostatin?

A

stop gastric secretions

100
Q

Histamine neural stimulus

A

acetylcholine

101
Q

Histamine hormonal stimulus

102
Q

What two things release histamine?

A

ECL cells
Histaminergic nerves

103
Q

Where are enteroendrocrine cells that release histamine located?

104
Q

Mode of action of Histamine

A

paracrine (local)

105
Q

Target organ for histamine

106
Q

Response to histamine

A

HCl secretion (up gastric acid)

107
Q

Motilin neural stimulus

A

acetylcholine

108
Q

What cell type releases motilin?

109
Q

Where are enterendocrine cells that release motilin located?

110
Q

Mode of action of motilin

A

neurocrine (neural cells)

111
Q

What 2 targets does motilin act on?

A

stomach + SI

112
Q

Motilin response

A

hormonal component to phase 3 migrating motor complexes (peristaltic contractions)

113
Q

Guanylin stimulus

A

salt ingestion

114
Q

What cell type releases guanylin?

A

goblet cells

115
Q

Where are enteroendocrine cells that release guanylin located?

A

large intestine

116
Q

Mode of action of guanylin

A

exocrine (into GI lumen)

117
Q

Target organ of guanylin

A

large intestine

118
Q

Response to Guanylin

A

stim. intestinal secretion

119
Q

Which two “other” family peptides work together to stimulate clearing of digesta?

A

guanylin + motilin

120
Q

What disease causes secretory diarrhea by E. coli toxin binding to guanylin receptor?

A

colibacillosis (traveler’s diarrhea)

121
Q

Colibacillosis is caused by E. coli toxin binding to _____ receptor = diarrhea

122
Q

Agonist-receptor interactions are similar to what?

A

many drugs

123
Q

Agonist properties are based on ____ and ____.

A

affinity
efficacy

124
Q

Affinity

A

ability of hormone to bind to receptor

125
Q

Efficiacy

A

ability of hormone to activate receptor

126
Q

Match affinity + efficacy of categories of hormone agonists:
(high/low/partial/none)

Full agonist
Partial agonist
Full antagonist

A

Full agonist: high affinity | high efficacy
Partial agonist: high affinity | partial efficacy
Full antagonist: high affinity | no efficacy

127
Q

Example of two hormones that increase in concentration at different times of digestion and can act on each other’s receptors.

A

Gastrin + CCK

128
Q

Increased ____ concentration occurs when the stomach fills, and as food enters SI, the _____ concentration increases, decreasing the efficacy of _____ at its receptor ____.

A

gastrin
CCK
gastrin
CCKB

129
Q

What is the overall result of the varying concentrations of gastrin + CCK able to act on each other’s receptors?

A

entry of digesta in duodenum slows outflow from stomach

130
Q

Example of stimulus-response coupling

A

crypt fluid secretion

131
Q

The response to an agonist is usually dependent on ________.

A

2nd messengers

132
Q

2 main categories of intracellular messengers

A
  1. cyclic nucleotides (cAMP/cGMP)
  2. intracellular Ca2+ mobilization
133
Q

Process of cyclic nucleotide messengers when an agonist binds

A
  1. receptor stim. ATP/GTP
  2. converted to cAMP/cGMP
  3. protein kinase A/G activated
    = secretion of Cl- + HCO3-
134
Q

How long do the effects of cyclic nucleotide messengers last?

A

minutes to hours

135
Q

Example of cyclic nucleotide messenger

A

VIP neurotransmitter (stim. intestinal secretion)

136
Q

Clinical relevance: ______ are the main intracellular messengers in intestinal epithelia stimulated by _______ from pathogenic bacteria.

A

cyclic nucleotides
enterotoxins

137
Q

Pathological: in excess, cyclic nucleotides cause what?

A

secretory diarrhea

138
Q

Intracellular Ca2+ mobilization (2nd messenger) is (shorter/longer) acting than cyclic nucleotides.

139
Q

Intracellular Ca2+ mobilization process when an agonist binds

A

Receptor increases intracell. Ca2+ (direct via protein kinase C or calmodulin
= epithelial fluid secretion

140
Q

How long do the effects of intracellular Ca2+ mobilizations last?

A

seconds to minutes

141
Q

Example of intracellular Ca2+ mobilization

A

cholinergic neural stim. of intestinal secretions

142
Q

(Cyclic nucleotide / intracellular Ca2+ mobilization) second messenger method is not used by many pathogens.

A

intracellular Ca2+ mobilization

143
Q

Systemic hormones don’t originate from ____.

144
Q

_____ hormones are systemic hormones.

145
Q

Two types of adrenal hormones (systemic)

A

epinephrine
adrenocorticosteroids

146
Q

Two sub-types of adrenocorticosteroids

A

aldosterone
glucocorticoids

147
Q

Epinephrine uses (PSNS/SNS) action via adrenergic receptors.

148
Q

3 responses to epinephrine

A
  1. down motility
  2. up absorption
  3. down GI blood flow
149
Q

Aldosterone increases ____ absorption in the colon / salivary duct.

150
Q

What 2 things increase due to aldosterone production?

A
  1. Na+ channels (ENAC)
  2. Na+ pump
151
Q

Aldosterone has the same effect in _____ as in the colon/salivary duct.

A

distal tubule of kidney

152
Q

What 3 responses occur from glucocorticoid secretion?

A
  1. up Na/K ATPase
  2. down prostaglandin tone
  3. suppress immune system
153
Q

Submucosal control is (systemic/local).

A

local (paracrine)

154
Q

In a non-pathological state, prostaglandins promote what 3 things?

A
  1. motility
  2. secretion
  3. vasodilation (up flow)
155
Q

In a pathological state, submucosal control causes increase in _____ & ____, leading to what 2 responses?

A

WBCs & prostaglandins
diarrhea & intestinal muscle spasms

156
Q

What are the 4 cell types under submucosal control?

A
  1. fibroblasts
  2. macrophages
  3. PMNs + eosinophils
  4. mast cells
157
Q

What cell type is the major source of prostaglandins in the physiological state under submucosal control?

A

fibroblasts

158
Q

Fibroblasts produce prostaglandins when there is ____ damage for what purpose?

A

mucosal
protective: up flow + secretion = flush & repair

159
Q

What cell type produces just prostaglandins under submucosal control?

A

macrophages

160
Q

What two substances do PMN’s & eosinophils produce under submucosal control?

A

prostaglandins
serotonin

161
Q

What cell type is aligned with effector neurons in intestine and release histamine?

A

mast cells

162
Q

Which cell type under submucosal control has a role in allergic states?

A

mast cells

163
Q

Histamine release from mast cells causes what?

A

increased fluid secretion = “wash away” antigens

164
Q

Why do food allergies occur?

A

up food sensitivity to food antigen = diarrhea

165
Q

Term for “seizing & conveying of food into the mouth”

A

Prehension

166
Q

Cattle prehension organ

A

tongue (grasp grass + scoop grain)

167
Q

Sheep prehension organs

A

tongue + cleft upper lip
graze closer to ground

168
Q

Horse prehension organ

A

mobile upper lip (fine motor movements)

169
Q

Pig prehension organ

A

pointed lower jaw (root/shovel)

170
Q

How do herbivores & omnivores drink?

A

via suction

171
Q

How to carnivore undergo prehension?

A

tearing movements (teeth, jaws, head)

172
Q

How to carnivores drink?

173
Q

4 functions of mastication

A
  1. reduces food size
  2. up surface area
  3. break cellulose (more starch available)
  4. mixes food w/ saliva
174
Q

What 3 things does mixing food with saliva add to it for mastication?

A

buffers
enzymes
mucous

175
Q

What is the first step of mastication?

A

biting smaller bits (reduce size) to increase surface area

176
Q

Herbivores masticate by ________ to increase surface area.

A

grinding of plant matter

177
Q

Ruminants grind plant matter during initial intake and ______.

A

rumination

178
Q

Cheek teeth of herbivores are (hypsodont/brachydont) meaning _____.

A

hypsodont
continuously growing

179
Q

What kind of teeth have rough table surface & lateral + vertical movements of the jaw?

A

cheek teeth

180
Q

Carnivores masticate only to ______.

A

reduce food to swallowing size

181
Q

Omnivores masticate on _____ diet while gulping on _____ diet.

A

plant
carnivorous

182
Q

What condition do lateral + circular movements cause on horses?

A

“points” on outer upper arcade & inner lower arcade

183
Q

What is the main sign of “points” on teeth? How is it treated?

A

dropping food
float teeth

184
Q

What tools are used to float horse teeth?

A

long handled rasps to grind down teeth

185
Q

2 signs of malocclusion

A

weight loss
drop food

186
Q

Malocclusion occurs when maxillary arcade (overgrows/stops growing) and mandibular arcade (overgrows/stops growing).

A

overgrow
stops growing

187
Q

How do you treat malocclusion horses?

A

soak pelleted horse feed in water = “gruel” so they can eat

GI Physiology (6 decks)

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