PNB 2265 EXAM 3 QUESTIONS AND
ANSWERS
Integrated-meal-response---ans---path-of-food-from-mouth-to-rectum
Integrated-meal-response-phases---ans---cephalic
gastric
intestinal
colonic
Two-parts-of-GI-tract---ans---alimentary-canal
accessory-organs
Alimentary-canal---ans---mouth
esophagus
stomach
small-intestines
large-intestines
rectum
Accessory-organs-of-GI-trac---ans---salivary-glands
liver
pancreas
gallbladder
Peritoneum---ans---serous-membrane-that-surrounds-GI-system-that-is-different-from-
others-bc-it-folds-in-on-itself-and-btwn-the-folds-are-fat-deposits
-made-of-parietal-and-visceral-with-peritoneal-fluid-between
Parietal-peritoneum---ans---layer-of-serous-membrane-that-lines-the-walls-of-the-
abdominal-cavity
Visceral-peritoneum---ans---layer-of-serous-membrane-that-covers-the-surface-of-organs
,Order-of-tissue-layers-in-GI-tract-(wall-to-lumen)---ans---serosa
muscularis
submucosa
mucosa
Serosa---ans---outer-layer-of-tube-that-is-connective-tissue-wrapper-that-holds-things-
together,-protects-them,-and-is-site-of-attachment
Muscularis-externa---ans---smooth-muscle-layer-that-has-two-layers,-one-longitudinal-
outer-layer-and-one-circular-inner-layer-with-a-myenteric-plexis-layer-btwn
Muscularis-externa-layers-(lumen-to-outer)---ans---circular-layer
myenteric-plexis
Longitudinal-layer
Myenteric-plexis---ans---nerve-tissue-layer-btwn-the-layers-of-the-muscularis-externa-that-
controls-smooth-muscle-contraction-and-is-under-involuntary-control-by-parasympathetic-
stimulation
Longitudinal-layer-muscularis-externa---ans---outer-layer-that-gives-you-contractions-that-
will-make-the-tube-shorter-or-longer-(controls-length)
Circular-layer-muscularis-externa---ans---inner-layer-that-controls-radius-of-the-tube
Submucosa---ans---loose-connective-tissue-that-binds-things-together.-Has-large-blood-
vessels,-large-lymphatic-vessels-(galt),-and-nerves
Galt---ans---submucosa-(gut)-associated-lymphatic-tissue-that-has-a-lot-of-immune-cells-
since-this-is-a-point-of-entry-for-pathogens
Mucosa-layers---ans---muscularis-mucosae
lamino-propria
epithelium-layer
Muscularis-mucosae---ans---mucosa-layer-that-is-the-muscle-part-that-shapes-the-surface-
of-the-mucosal-layer
Lamina-propria---ans---connective-tissue-mucosal-layer-with-tiny-vessels-(capillaries)-and-
small-lymphatic-vessels
Epithelium-layer-(mucosa)---ans---mucosa-layer-closest-to-lumen-that-has-specializations-
depending-on-where-in-the-GI-tract
-has-enterocytes,-enteroendocrine-cells,-and-mucin-producing-cells
Submucosal-plexus---ans---nerves-in-the-submucosa-layer
, Enterodendocrine-cells---ans---secretory-cells-in-epithelia-of-mucosa
Enterocytes---ans---cells-that-do-absorption-in-epithelia-of-mucosa
Mucin-producing-cells---ans---mucous-producing-cells-in-epithelia-of-mucosa
Peristalsis---ans---motility-of-GI-tract-that-produces-forward-movment
-contraction-of-smooth-muscle-behind-bolus-to-create-high-pressure-behind-and-low-
pressure-in-front
-found-in-esophagus,-stomach,-weak-in-small-intestines,-infrequently-in-large-intestine
Segmentation---ans---Coordinating-contractions-in-front-and-behind-to-create-mixing
-proximal-and-distal-contractions-
-faster-frequency-behind-to-still-slightly-push-things-forward
-primarily-in-small-intestines
Phasic-contractions---ans---quick-contractions-that-produce-movement-(peristalsis-and-
segmentation)
Tonic-contractions---ans---smooth-muscles-contracts-and-stays-contracted-to-prevent-
backflow
-is-in-sphincters
Smooth-muscle-contractions---ans---can-contract-more-than-other-muscles-due-to-
diagonal-filaments-and-doesn't-have-to-worry-about-refractory-period
Smooth-muscle-contraction-mechanism---ans---Uses-MLCK-to-phosphoryalte-myosin-
chain-and-speed-up-ATP-hydrolysis-and-promote-contraction
-doesnt-have-tropomyosin-or-myosin-head
Myosin-Light-Chain-Kinase-(MLCK)---ans---enzyme-that-when-active-can-phosphorylate-
myosin-chain-and-speed-up-ATP-hydrolysis-in-smooth-muscle-to-promote-contraction
-anything-that-increases-its-activity-promotes-contraction
MLCK-regulation---ans----Ca-activates-it-and-promotes-contraction
-cAMP-inhibits-it-and-causes-relaxation
Myosin-light-chain-phosphatase-(MLCP)---ans---removes-a-phosphate-from-myosin-chain-
and-is-inhibitory-to-smooth-muscle-contration
Phosphodiesterase---ans---breaks-down-cAMP
Which-membrane-does-secretion-in-GI-tract---ans---apical-membrane,-closest-to-lumen
Which-membrane-does-absorption-in-GI-tract---ans---basal-membrane
ANSWERS
Integrated-meal-response---ans---path-of-food-from-mouth-to-rectum
Integrated-meal-response-phases---ans---cephalic
gastric
intestinal
colonic
Two-parts-of-GI-tract---ans---alimentary-canal
accessory-organs
Alimentary-canal---ans---mouth
esophagus
stomach
small-intestines
large-intestines
rectum
Accessory-organs-of-GI-trac---ans---salivary-glands
liver
pancreas
gallbladder
Peritoneum---ans---serous-membrane-that-surrounds-GI-system-that-is-different-from-
others-bc-it-folds-in-on-itself-and-btwn-the-folds-are-fat-deposits
-made-of-parietal-and-visceral-with-peritoneal-fluid-between
Parietal-peritoneum---ans---layer-of-serous-membrane-that-lines-the-walls-of-the-
abdominal-cavity
Visceral-peritoneum---ans---layer-of-serous-membrane-that-covers-the-surface-of-organs
,Order-of-tissue-layers-in-GI-tract-(wall-to-lumen)---ans---serosa
muscularis
submucosa
mucosa
Serosa---ans---outer-layer-of-tube-that-is-connective-tissue-wrapper-that-holds-things-
together,-protects-them,-and-is-site-of-attachment
Muscularis-externa---ans---smooth-muscle-layer-that-has-two-layers,-one-longitudinal-
outer-layer-and-one-circular-inner-layer-with-a-myenteric-plexis-layer-btwn
Muscularis-externa-layers-(lumen-to-outer)---ans---circular-layer
myenteric-plexis
Longitudinal-layer
Myenteric-plexis---ans---nerve-tissue-layer-btwn-the-layers-of-the-muscularis-externa-that-
controls-smooth-muscle-contraction-and-is-under-involuntary-control-by-parasympathetic-
stimulation
Longitudinal-layer-muscularis-externa---ans---outer-layer-that-gives-you-contractions-that-
will-make-the-tube-shorter-or-longer-(controls-length)
Circular-layer-muscularis-externa---ans---inner-layer-that-controls-radius-of-the-tube
Submucosa---ans---loose-connective-tissue-that-binds-things-together.-Has-large-blood-
vessels,-large-lymphatic-vessels-(galt),-and-nerves
Galt---ans---submucosa-(gut)-associated-lymphatic-tissue-that-has-a-lot-of-immune-cells-
since-this-is-a-point-of-entry-for-pathogens
Mucosa-layers---ans---muscularis-mucosae
lamino-propria
epithelium-layer
Muscularis-mucosae---ans---mucosa-layer-that-is-the-muscle-part-that-shapes-the-surface-
of-the-mucosal-layer
Lamina-propria---ans---connective-tissue-mucosal-layer-with-tiny-vessels-(capillaries)-and-
small-lymphatic-vessels
Epithelium-layer-(mucosa)---ans---mucosa-layer-closest-to-lumen-that-has-specializations-
depending-on-where-in-the-GI-tract
-has-enterocytes,-enteroendocrine-cells,-and-mucin-producing-cells
Submucosal-plexus---ans---nerves-in-the-submucosa-layer
, Enterodendocrine-cells---ans---secretory-cells-in-epithelia-of-mucosa
Enterocytes---ans---cells-that-do-absorption-in-epithelia-of-mucosa
Mucin-producing-cells---ans---mucous-producing-cells-in-epithelia-of-mucosa
Peristalsis---ans---motility-of-GI-tract-that-produces-forward-movment
-contraction-of-smooth-muscle-behind-bolus-to-create-high-pressure-behind-and-low-
pressure-in-front
-found-in-esophagus,-stomach,-weak-in-small-intestines,-infrequently-in-large-intestine
Segmentation---ans---Coordinating-contractions-in-front-and-behind-to-create-mixing
-proximal-and-distal-contractions-
-faster-frequency-behind-to-still-slightly-push-things-forward
-primarily-in-small-intestines
Phasic-contractions---ans---quick-contractions-that-produce-movement-(peristalsis-and-
segmentation)
Tonic-contractions---ans---smooth-muscles-contracts-and-stays-contracted-to-prevent-
backflow
-is-in-sphincters
Smooth-muscle-contractions---ans---can-contract-more-than-other-muscles-due-to-
diagonal-filaments-and-doesn't-have-to-worry-about-refractory-period
Smooth-muscle-contraction-mechanism---ans---Uses-MLCK-to-phosphoryalte-myosin-
chain-and-speed-up-ATP-hydrolysis-and-promote-contraction
-doesnt-have-tropomyosin-or-myosin-head
Myosin-Light-Chain-Kinase-(MLCK)---ans---enzyme-that-when-active-can-phosphorylate-
myosin-chain-and-speed-up-ATP-hydrolysis-in-smooth-muscle-to-promote-contraction
-anything-that-increases-its-activity-promotes-contraction
MLCK-regulation---ans----Ca-activates-it-and-promotes-contraction
-cAMP-inhibits-it-and-causes-relaxation
Myosin-light-chain-phosphatase-(MLCP)---ans---removes-a-phosphate-from-myosin-chain-
and-is-inhibitory-to-smooth-muscle-contration
Phosphodiesterase---ans---breaks-down-cAMP
Which-membrane-does-secretion-in-GI-tract---ans---apical-membrane,-closest-to-lumen
Which-membrane-does-absorption-in-GI-tract---ans---basal-membrane
