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Phys 208 > Gastrointestinal > Flashcards

Flashcards in Gastrointestinal Deck (160)
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1
Q

what are accessory organs? Examples?

A

secrete contents into lumen of gut; salivary glands, liver, gallbladder, pancreas

2
Q

what are the 3 salivary glands?

A

parotid, sublingual, submandibular

3
Q

liver secretes these things

A

bile acids, bicarbonates

4
Q

stores liver secretions

A

gallbladder

5
Q

pancrease secretes pancreatic enzymes and bicarbonates into ___

A

duodenum

6
Q

three parts of small intestine:

A

duodenum–>jejunu–>ileum

7
Q

these bacteria contribute to digesting fibre, provide essential nutrients, prevent pathogenics from colonizing

A

commensal

8
Q

these increase growth of commensal bacteria

A

probiotics

9
Q

separate portions of GI

A

sphincters

10
Q

mjority of absorption take place in

A

duodenum of small intestine

11
Q

___part of anus is made up of skeletal muscle

A

external

12
Q

myenteric and submucous plexuses involve ______

A

nerve ganglia (enteric nerves)

13
Q

deep muscular plexus located in ____ muscle layer

A

circular

14
Q

pacemakers found in ___ and ___ plexuses

A

myenteric; deep

15
Q

what are the 5 hormones secreted by endocrine cells?

A

gastrin, CCK, secretin, GIP, motilin

16
Q

outer connective tissue covering the digestive tract that secretes watery fluid for lubrication

A

serosa

17
Q

this layer of GI is where blood and lymph vessels reside, responsible for distensibility and elasticity

A

submucosa

18
Q

sympathetic and parasymp activity is example of ___ innervation, enteric nervous sys (nerve plexuses) is example of ___

A

extrinsic; intrinsic

19
Q

slow wave potential is also known as:

A

Basic Electrical rhythm

20
Q

ICC connected by ____, to allow ____

A

gap junctions; syncytium

21
Q

destruction of ICCs in ___ leads to impaired gastric motility, called:

A

diabetes; gastroparesis

22
Q

what are the ICC functions?

A

generate slow wave activity, coordinate active propagation of slow waves, transduce motor neural inputs from ENS to muscle, sense stretch

23
Q

a receptor-type tyrosine kinase binding to ligand stem cell factor

A

c-kit

24
Q

ICCs in stomach beat __ waves/min, in duodenum __ waves/min

A

3; 12

25
Q

challenges in GI?

A
  • moving food down tube at appropriate speed without blockage
  • digest food without digesting self
  • match fluid input/output
  • keep bacteria/viruses from entering
26
Q

how does GI keep bacteria/viruses enter body?

A

oral cavity sanitizes; ilium of sm intestine proliferate good bacteria which is colonizing large intestine

27
Q

___ L of fluid/day enter small intestine from ingestion and GI secretions of water

A

7-10

28
Q

malabsorption of electrolytes and water in sm intestine lead to _____

A

diarrheic stool

29
Q

motility requires ____ and ___ for muscle contraction

A

ICCs; enteric nerves

30
Q

major functions of digestive sys?

A

mvmt/mixing thru alimentary tract, secrete digestive juices/digestion, absorption, circulation blood carry away nutrients, nervous/hormone reg, mucosal immune function, excretion

31
Q

___ system uses hormonal and neurotrans communication methods with ____

A

endocrine; stomach

32
Q

this part of GI referred to as “reservoir”

A

large intestine

33
Q

friendly bacteria reside here

A

appendix

34
Q

GI is ___ to external enviro

A

continuous

35
Q

equation of energy balance?

A

food intake-energy loss = energy expenditure

36
Q

molecules are broken down by ___

A

hydrolysis

37
Q

nutrients are extracted by __ and ___ digestion

A

mechanical; chemical

38
Q

stim depolarization of basal membrane by:

A

stretch, acetylcholine, parasymp

39
Q

inhibit basal membrane potential by:

A

norepinephrine, sympathetics, nitric oxide, VIP

40
Q

VIP stands for:

A

Vaso-active Intestinal polypeptide

41
Q

what are the diff motility patterns?

A

peristalsis, segmentation, mass mvmt, migrating motor complex

42
Q

peristalsis occurs in __

A

esophagus

43
Q

motor pattern involved with fasting, and stimulated by increase in levels of motilin

A

migrating motor complex

44
Q

proteins/electrolytes contained in saliva

A

lingual lipase, amylase, mucins, IgA, lysozyme, lactoferrin, bicarbonate

45
Q

you secrete about ___mL saliva per day

A

1500

46
Q

parasympathetic input to salivary glands causes _____, sympathetic input causes _____

A

abundant flow; mucus enrichment (less flow)

47
Q

damage to ____ cause atrophy in salivary glands

A

parasymp

48
Q

damage to salivary glands referred to as:

A

xerostomia

49
Q

v salivary secretion caused by:

A

sleep, fatigue, dehydration, fear

50
Q

what drugs can inhibit salivary gland secretion?

A

antidepressants, antihypertensives, psychotropics

51
Q

syndrome involving autoimmune attack of salivary glands

A

Sjogren’s syndrome

52
Q

condition characterized by difficulty in swallowing, food getting stuck, and reduced inhibitory nerve input

A

achalasia

53
Q

relaxation mainly due to ___, contraction by ____

A

NO; ACh

54
Q

what is GERD?

A

gastroesophageal reflux disease; characterized by esophagitis, columnar cells replace squamous epithelium, adenocarcinoma

55
Q

GERD treatments?

A

proton pump inhibitors, H2 histamine receptor antagonists

56
Q

How is primary peristaltic wave initiated? How is secondary initiated?

A

swallowing centre (medulla); distension

57
Q

functions of stomach?

A

store ingested food, secrete HCl and enzymes begin protein digestion,

58
Q

where is gastrin secreted?

A

from endocrine cells called G-cells in antrum (pyloric gland)

59
Q

where is ghrelin secreted?

A

oxyntic gland

60
Q

mix and pulverize food

A

antral pump

61
Q

receptive relaxation mediated by ___ is responsible for constant ___

A

NO; pressure/volume

62
Q

stomach can extend to about ____ L

A

1

63
Q

storage involves weak mixing in __ and __

A

fundus; body

64
Q

mixing involves strong ___ peristaltic contractions

A

antral

65
Q

___ hormone increases contractility of antral smooth muscle

A

gastrin

66
Q

presence of ____ shut down gastric emptying in a negative feedback loop; this is called ___ reflex

A

gastric chyme in duodenum (decreased pH), presence of lipids, osmolites, distension in duodenum; enterogastric

67
Q

neural and hormonal factors in enterogastric reflex?

A

secretin (acid), cholecystokinin (fats), GIP (gastric inhibitory peptide–>osmolarity change, carbs)

68
Q

GIP promotes release of ___ from pancreatic __ cells

A

insulin; beta

69
Q

gastric enzymes such as ____ are secreted from oxyntic mucosa

A

pepsinogen (inactive form of pepsin), gastric lipase

70
Q

ghrelin and gastrin are secreted into ___

A

blood

71
Q

____ cells are responsible for acid secretion and intrinsic factor

A

parietal

72
Q

intrinsic factor is important for ____

A

blood development

73
Q

___ cells are responsible for release of pepsinogen, gastric lipase

A

chief

74
Q

mucus created by surface ___ and neck ___ cells

A

epithelium; mucous

75
Q

stem cells replenish epithelial cells every ____ days

A

3-4

76
Q

functions of HCl:

A

digestion, activate pepsinogen, kill bacteria

77
Q

function of intrinsic factor

A

Vit B12 absorption (cobalamine), lack leads to pernicious anemia

78
Q

HCl and intrinsic factor are secreted by:

A

parietal cell

79
Q

parietal cells have lots of ___

A

mitochondria (ATP to drive proton pump), tubulovesicles (H/K ATPase)

80
Q

activation of acid secretion is by ____

A

histamine, acetylcholine, gastrin binding to respective receptors at basolateral membrane

81
Q

IF and acid secretion increases with the fusion of ___ and ___

A

tubulovesicles; intracell canaliculi

82
Q

what is alkaline tide?

A

at max acid secretion, bicarbonate in blood supply of stomach

83
Q

what are three phases of gastric secretions?

A

cephalic influences, gastric phase, intestinal phase

84
Q

cephalic contribute __% total acid secretion, gastric __%, intestinal __%

A

30; 50; 5-10

85
Q

enzymes in ___ not essential for life, enzymes from ____ are essential

A

stomach; pancreas

86
Q

how does stomach not destroy itself with strong acid?

A

tight junction provide barrier and prevent leakage, luminal mem not permeable to H, layer of mucus offer protection (has bicarbonate), damaged cells rapidly replaced every 3 days

87
Q

breakdown of the mucosal barrier results in a ____

A

peptic ulcer

88
Q

wht causes peptic ulcers?

A

H. pylori, chem exposure, stressful situations (^ gastric secretions)

89
Q

how to cure h. pylori peptic ulcer?

A

antibiotic+proton pump inhibitor

90
Q

gastric secretion during intestinal phase is inhibited by presence of _____ or _____

A

lipids; low pH

91
Q

what are secretions by the small intestine?

A

mucus and water, GI hormones, lysozyme, no digestive enzymes (except enterokinase)

92
Q

secretin acts on ____ to secrete

A

pancreatic ducts; bicarbonate

93
Q

enterokinase is a _____ enzyme

A

brush border

94
Q

enterokinase cleaves __

A

trypsinogen

95
Q

“the master enzyme” for all pancreatic proteases

A

trypsin

96
Q

primary bile acid comes from____

A

cholesterol (made in liver hepatocytes)

97
Q

secondary bile acid comes from ____

A

colonic bacteria enzymes

98
Q

primary bile acids are conjugated with ____

A

taurine, glycine

99
Q

what are the two types of gallstones?

A

Ca bilirubenates, cholesterol stones (most common)

100
Q

what are factors that promote formation of gallstones?

A

bile stasis, chol. supersaturation in bile, nucleation factors

101
Q

symptoms of gallstones?

A

pain below right scapula after eating oily/fatty meal

102
Q

process where fat globs are turned into droplets so that there’s more SA for pancreatic lipase to act

A

emulsification

103
Q

bile secrete ___g bile per day

A

0.2

104
Q

need ___ to absorb vit ADEK

A

bile salts

105
Q

what does asbt stand for?

A

apical sodium dependent bilesalt transporter

106
Q

asbt found at ____

A

terminal ileum

107
Q

asbt is important for ____ circulation

A

enterohepatic

108
Q

colonic bacteria do these two things to bile salts:

A

1) deconjugate bile salts

2) remove hydroxyl radical

109
Q

fat malabsorption results in:

A

diarrhea

110
Q

aggregates of bile salts is called:

A

micelles

111
Q

production of bile is ^ by:

A

secretin, stim of vagus nerves

112
Q

circular folds in small intestine called:

A

plicae circularis

113
Q

most absorption happen at ____, most secretion at ___

A

villi; crypts

114
Q

small lymphatic vessels are called:

A

lacteals

115
Q

villi, crypts, plicae circularis, microvilli on apical mem of sm intestine ^ SA by ___x

A

600

116
Q

“the body’s biochem factory”

A

liver

117
Q

enzyme that resumes fat digestion by positioning lipase near O/W interface

A

colipase

118
Q

blood supply to liver ___% from hepatic portal vein, ___% from hepatic artery

A

75; 25

119
Q

hepatic portal vein and artery blood mix at ____

A

hepatic sinusoids

120
Q

majority of cells in liver are:

A

hepatocytes

121
Q

these cells store vit A

A

stellate cells

122
Q

cells that are phagocytic immune cells

A

Kupffer cells

123
Q

hepatic artery, hepatic portal vein and bile duct form the _____

A

hepatic portal triad

124
Q

things that come into liver from portal vein?

A

bile salts, nutrients, drugs, foreign substances

125
Q

things that come into liver from hepatic artery

A

O2, nutrients, bilirubin, hormones, drugs

126
Q

things that come out of liver thru bile

A

bile salts, bilirubin, water/ions, cholesterol

127
Q

things that come out of liver thru hepatic vein

A

glucose, plasma proteins, urea, vit. D, metabolites

128
Q

what does liver store?

A

glycogen, fats, Fe, Cu, vitamins

129
Q

liver synth plasma proteins such as

A

albumin, clotting factors

130
Q

“fuzzy coat” of sugar moieties, glycosylated proteins

A

glycocalyx

131
Q

pancreatic amylase digests starch into ______

A

maltose, maltriose, short oligos

132
Q

sugars are digested by ____

A

brush border enzymes in microvilli of small intestine

133
Q

examples of brush border enzymes?

A

sucrase, isomaltase

134
Q

gluc and gal are transported by ______ carrier protein; it is a ____ active transporter

A

SGLT-1; secondary

135
Q

fruc absorbed by ___ which is a _____ transport process

A

GLUT5; passive

136
Q

basolateral membrane has GLUT ___ and GLUT ___

A

2; 5

137
Q

what does PEPT1 transport?

A

di-tri peptides, along with H+ ion

138
Q

3 regions of large intestine?

A

ascending, transverse, descending

139
Q

first part of colon??

A

cecum

140
Q

discontinuous longitudinal muscle in large intestine is called:

A

tenia coli

141
Q

mucosal folds in large intestine called:

A

haustra

142
Q

motility of large intestine includes:

A

haustral contractions, mass mvmts

143
Q

point of appendix?

A

refresh bacteria in colon ater large bouts of diarrhea

144
Q

motility dysfunction in colon characterized by severe constipation, dilation of colon, no myenteric plexus ganglion

A

mega-colon-Hirschprung’s disease

145
Q

two defecation reflexes:

A

intrinsic (weak), parasymp (strong)

146
Q

in defecation reflex, there is ___ of rectum and relaxation of _____

A

contraction; internal anal sphincter

147
Q

parasymp reflex in ____ nerves

A

sacral, pelvic

148
Q

what is the largest lymphoid organ in body?

A

gut-associated lymphoid tissue

149
Q

lymphoid nodules in the submucosa connective tissue are called:

A

Peyer’s Patch

150
Q

associated with colon cancer

A

polyps (tubular adenoma)

151
Q

symptoms of polyps?

A

blood in feces, diarrhea

152
Q

bacteria in large intestine convert bilirubin to ____

A

stercobilin

153
Q

normal range of glucose in plasma?

A

3.9-6mmol/L

154
Q

liver shuttles XS gluc into _____, and turned into ____

A

hepatocytes; glycogen

155
Q

short term regulation of hunger is provided by _____

A

GI hormones

156
Q

long term regulation of hunger is provided by ______

A

leptin and insulin

157
Q

inhibitory signals for eating?

A

leptin, insulin, PYY, CCK

158
Q

leptin acts on _____ nucleus of hypothalamus by decreasing release of ___ and _____ protein

A

arcuate; NPY; agouti

159
Q

leptin stimulates release of ___

A

MSH (melanocyte stimulating hormone)

160
Q

insulin stimulates ___ storage and increases ___ secretion; suppresses ___ release in hypothalamus

A

fat; leptin; NPY