Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Histo Exam 3 > Digestive System (Upper GI) > Flashcards

Digestive System (Upper GI) Flashcards

(92 cards)

Start Studying
1
Q

what are the components of the digestive system?

A

oral cavity & alimentary canal

  • esophagus
  • stomach
  • small & large intestines
  • extrinsic glands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the layers of the digestive system?

A

GI system is a layered hollow tube with

  • mucosa
  • submucosa
  • muscularis exerna
  • serosa
  • adventitia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what layer of the GI system is continuous with mesentery?

A

serosa

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

what layer of the GI system is fixed to the walls of the abdominal cavity?

A

adventitia

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

in general, what does the GI system do to digest?

A

secretes enzymes and hormones that function in the digestive process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

lining of the esophagus is what type of cells?

A

stratified squamous nonkeratinized epithelium

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

in the esophagus, what secretes mucous?

A

esophageal cardiac glands in the lamina propia

esophageal glands proper in the submucosa

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

esophageal glands proper primarily secrete mucous but what else do they secrete?

A

lysozyme

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

in the esophagus, how many layers is the muscularis mucosae and how are the striations arranged?

A

there is a single longitudinal layer of smooth muscle

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

in the esophagus, the muscularis externa changes from what to what to what at each third?

A

upper third: striated muscle

middle third: smooth & striated

lower third: smooth muscle

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

function of the esophagus? what primarily is responsible fro this function?

A

conveys food bolus from pharynx to stomach - peristaltic activity of muscularis externa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

in the muscularis externa of the esophagus, where would you find the sphincters

A

pharyngoesophageal (upper) & gastroesophageal (lower) in muscularis externa

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

what is the general role of sphincters in the esophagus

A

a sphincter insures bolus is transported in 1 direction: towards the stomach

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

the specific role of the upper esophageal sphincter?

A

initiates swallowing

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

the specific role of the lower esophageal sphincter?

A

prevents acid reflux from stomach into esophagus

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

what can persistent acid reflux lead to?

A

gastroesophageal reflux disease (GERD)

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

aside from GERD, what else could acid reflux from stomach into the esophagus lead to?

A

it can lead to ulceration & difficulty swallowing => fibrosis & stricture of lower esophagus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is Barrett’s esophagus?

A

abnormal growth of intestinal-type cells (simple columnar) in the lower esophagus and its injured easily by stomach acid

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

what is a risk associated with Barrett’s esophagus

A

adenocarcinoma of esophagus with 3x greater incidence in males

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

if the esophageal hiatus in the diaphragm does not close entirely during development - results in ?

A

hiatal hernia

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

what “herniates” in a hiatal hernia?

A

portion of stomach can move into thoracic cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what signs could indicate you have a hiatal hernia?

A

difficulty swallowing, feeling “lump” in throat

reflux esophagitis, ulceration

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

the stomach (acidifies/alkalizes) food into viscous fluid known as _______

A

acidifies, chyme

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

stomach produces (in general)?

A

enzymes and hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what are the longitudinal folds of the mucosa & submucosa called?
rugae
26
in what circumstance would you not be able to see rugae?
when the stomach is distended
27
so gastric pits are literally pits in the stomach. which pits would be deeper and which would be more shallow?
the gastric pits are deepest in the pylorus and shallowest in the cardia
28
the cardia of the stomach has what type of glands? what does it secrete
tubular glands with coiled end and it secretes mucous
29
what portion of the stomach is a primary contributor to gastric juice?
the fundus
30
the fundus has what types of glands?
simple tubular glands
31
shallow gastric gland pits in the fundus would have an abundance of what type of cell(s)?
parietal & chief cells
32
what has similar epithelium to the fundus?
the body of the stomach
33
what structure in the stomach has deep gastric pits with branched glands
pylorus
34
what would you find in the pylorus?
primarily mucus secreting with occasional parietal cell G cells secreting gastrin
35
what are the layers of the gastric mucosa?
simple columnar lamina propria gastric glands muscularis mucosae
36
the simple columnar cells in the gastric mucosa are similar to (but should not be mistaken as) what? and what do they secrete?
the simple columnar cells are similar to goblet cells because they secrete mucous on the surface lining of the cells
37
what are the contents of the lamina propria in the gastric mucosa?
loose CT with smooth muscle, lymphocytes, plasma cells, mast cells & fibroblasts
38
how would you describe the muscularis mucosal layer of the gastric mucosa?
poorly defined inner circular layer outer longitudinal layer of smooth muscle occasionally an outermost circular layer (unique to GI)
39
what type of connective tissue does gastric submucosa have and what four things would you find in it?
dense irregular collagenous CT with fibroblasts, mast cells, lymphoid elements, and Meissner's plexus
40
how many layers would you find in the gastric muscularis externa and what would they be?
3 layers of smooth muscle: incomplete inner oblique thick middle circular (forms pyloric sphincter) outer longitudinal layer
41
what is the gastric muscularis externa responsible for?
mixing the gastric contents | emptying the stomach
42
what influences the stomach's emptying rate?
chyme characeristics (e.g. viscosity, pH, lipid content, osmolality, caloric density)
43
what the heck is gastric serosa???
covers external surface of stomach (per wiki = serous membrane)
44
so gastric glands (of fundus) are simple tubular & consist of 3 segments:
isthmus - connects gland to base of gastric pit neck base
45
what types of cells would you find along the gastric pits?
parietal, chief, mucous neck, enteroendocrine and regenerative cells
46
regenerative cells are primarily located where along the gland/pit and what do they do?
regenerative cells are primarily located on the neck and isthmus replace other cells in the gland, pit, & luminal surface
47
what do gastric surface lining cells contain
they have apically located mucinogen granules
48
what do surface lining cells secrete and what does it have a high concentration of
cloudy, thick, viscous mucous with high bicarbonate content
49
what is the purpose of having high bicarb in mucous?
in the stomach, it confers acid protection, coats surface epithelium (~100 micrometers thick)
50
do gastric surface lining cells live for a very long time?
they get renewed every 3-5 days
51
mucous neck cells are located where?
located at necks of gastric glands
52
mucous neck cells have (short/long) microvilli (apical/basal) mucous granules (diminished/prominent) Golgi and are (shorter/taller) cells than surface lining cells
``` mucous neck cells have short microvilli apical mucous granules prominent Golgi Shorter columnar cell than surface lining cells ```
53
what do mucous neck cells secrete? what stimulates it?
soluble mucous (thinner than surface lining mucous) upon vagal stimulation
54
what cells are pyramidal-shaped and are in the upper half of gastric glands?
parietal (oxyntic) cells
55
what do parietal cells stain in H&E?
red-pink, they're eosinophilic
56
parietal cells secrete what two compounds?
hydrochloric acid (HCl) and gastric intrinsic factor
57
what is gastric intrinsic factor used for
glycoprotein needed for the absorbtion of vitamin B12 in small intestine
58
parietal cells have intracellular _________ _______, which can only be seen by EM
tubulovesicular system
59
where would you find intracellular canaliculi and what are they?
they are in parietal cells | intracellular canaliculi - deep invaginations of the apical plasma membrane lined by microvilli
60
when parietal cells are stimulated to secrete HCl, number of microvilli (increases/decreases) complexity of tubulovesicular system (increases/decreases)
number of microvilli increase | complexity of tubulovesicular system decreases
61
what two molecules stimulate HCl secretion?
acetylcholine and gastrin
62
what increases the effects of acetylcholine & gastrin on parietal cells?
histamine binding to histamine H2 receptors | histamine produced by enterochromaffin-like cells in lamina propria around gastric glands
63
why do people take anti-acid drugs like cimetidine?
inhibits histamine-dependent acid secretion (drops acid secretion)
64
why do people take anti-acids like omeprazole?
because it binds to H+, K+-dependent ATPases and inactive acid secretion completely
65
describe how carbon dioxide (either from blood/parietal cells) ends up getting picked up by capillaries?
carbonic anhydrase combines CO2 with OH- ions => carbonic acid => bicarbonate = H+ bicarbonate diffuses out of cell and gets picked up by capillaries
66
what does the uptake of bicarb affect?
affects blood and mucous pH on the surface
67
what cells are pyramidal-shaped and in the lower half of the fundic glands?
chief (zymogenic) cells
68
what do chief cells stain in H&E?
blue/basophilic
69
what do chief cells secrete?
pepsinogen (zymogen form of pepsin) rennin precursors lipase precursors
70
chief cells have a lot of (basally/apically) located rER (supranuclear/subnuclear) Golgi (basal/apical) secretory granules (zymogen)
chief cells have a lot of basally located rER supranuclear Golgi apical secretory granules
71
enteroendocrine cells belong to a population of what type of cells?
diffuse neuroendocrine cells aka APUD cells
72
diffuse neuroendocrine cells (DNES) are also called?
APUD cells (amine precursor uptake & decarboxylation cells)
73
how many different types of enteroendocrine cells are there and how many hormones do each secrete?
there are greater than a dozen types, each type only secretes one hormone
74
gastric juices contain?
water, HCl, mucus, pepsin, lipase, rennin, & electrolytes
75
what is the acidity of gastric juice?
pH = 2.0
76
what gets activated by gastric juice and how does it facilitate it?
pepsinogen -> pepsin | gastric juice catalyzes the partial hydrolysis of proteins
77
gastric secretions are regulated by what?
they are regulated by the vagus nerve and hormones
78
secretin: who secretes it when is it secreted what does it stimulate?
duodenum secretes secretin @ pH < 4.5 stimulates pancreatic secretion of HCO3 & fluid chief cells secrete pepsinogen
79
gastrin: who secretes? what does it stimulate?
G cells in pylorus (small G17) & duodenal mucosa (large G34) secrete gastrin stimulates HCl secretion
80
somatostatin: who secretes? what does it affect?
D cells of pylorus & duodenum inhibits gastrin indirectly inhibits HCl secretion
81
Gastric inhibitory peptide (urogastrone) who secretes? what does it affect?
cells in duodenum & jejunum directly inhibits HCl secretion stimulates insulin release
82
hormone produced in duodenum & jejunum, | stimulates gallbladder contraction when fat is in small intestine
cholecystekinin (CKK)
83
hormone released cyclically (~ every 90 minutes) during fasting from cells in upper GI tract
motilin
84
what types of people are more likely to get gastritis?
more common in middle-aged/older individuals
85
what is the typical etiology of gastritis?
unknown
86
what is the range of problems gastritis could lead to?
superficial or affect the entire thickness causing mucosal atrophy
87
what is abnormal in patients with Zollinger-Ellison syndrome?
patients have gastrin secreting tumors (ups HCl), hypertrophy of fundus => stomach acid, diarrhea
88
Gastric/peptic ulcers are defined as what
areas of mucosa (gastric/duodenal) destroyed by gastric secretions
89
in what parts of the GI system are peptic ulcers commonly found?
cardiac & pyloric regions & first part of duodenum
90
what are causes of gastric ulcers (6 possible causes)
``` excess HCl secretions nervous irritation decreased vascular supply reduced mucus secretion infection (Helicobacter pylori) NSAIDS (e.g. aspirin) ```
91
possible treatments for ulcers?
``` antibiotics stress management eliminating alcohol eliminating asprin/NSAIDS eliminating cigarette use antacids or drugs that inhibit gastric secretions ```
92
what are the infection phases of H. pylori?
active phase - H. pylori increases gastric pH by producing ammonia via urease stationary phase - bacteria attach to fucose (< real thing) containing receptors on mucus cell surface in pylorus bacteria releases proteases that kills surface cells colonization phase - bacteria detach & replicate in mucus blanket

Histo Exam 3 (6 decks)

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