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Flashcards in Stomach and Esophagus Deck (52)
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1
Q

What are the components of the ailmentary canal?

A

oral cavity, pharynx, esophagus, stomach, small intestine, large intestine, and anal canal

2
Q

what are the principal organs associated with the ailmentary canal?

A

tongue, teeth, salivary glands, pancreas, liver, gallbladder

3
Q

What is the function of the mucosa epithelium of the ailmentary canal?

A

protective, secretory, or absorptive

4
Q

what does the lamina propria of the mucosa layer of the ailmentary canal contain? (tissue/cells)

A

loose CT with many capillaries; often contains diffuse or nodular lymphatic tissue referred to as gut - associated lymphatic tissue (GALT); may contain glands continuous with epithelium (mucosal glands)

5
Q

what does the muscularis mucosae layer of the alimetary canal contain? (in the mucosa layer)

A

thin layer of smooth muscle, sometimes with inner circular and outer longitudinal components

6
Q

Why type of tissue is found in the ailmentary canal submucosa?

A

coarse collagenous CT (dense irregular) with blood vessels, lymphatic vessels, and nerves
AND ganglion cells of the submucosal plexus = Meissners

7
Q

where does the submucosa layer of the ailmentary canal contain glands?

A

only in the esophagus and duodenum

8
Q

Describe the muscle layers in the muscularis externa layer of the ailmentary canal

A

usually two layers: inner circular and outer longitudinal, which provide for luminal and longitudinal constriction, respectively;

the stomach has 3 layers (inner oblique layer is added)

9
Q

Where is the ganglia of myenteric (Auerbach’s) plexus found?

A

between the (inner) circular and (outer) longitudinal layers of the muscularis externa layer of the ailmentary canal

10
Q

what is the function of the ganglia myenteric? what system do they belong to?

A

belong to the intrinsic enteric component of the autonomic nervous system;

Function = integrated networks regulate peristaltic muscular contractions and secretory functions of mucosal and submucosal glands

11
Q

what is the outermost layer of the ailmentary canal?

A

serosa or adventitia (fibrosa)

12
Q

Describe the serosa layer of the ailmentary canal

A

outer layer of connective tissue covered by a simple squamous epithelium called mesothelium

13
Q

Describe the adventitia fibrosa layer of the ailmentary canal. where is it found?

A

when the organ (ie: esophagus) is NOT suspending in the peritoneal cavity, there is no medothelial covering = adventitia fibrosa

14
Q

what is the function of the oropharynx? what does it transmit?

A

provides access to esophagus; carries both air and food

15
Q

Describe the mucosa layer of the oropharynx

A

epithelium = stratified squamous non-keratinized
lamina propria = loose CT with elastic fibers, some mucous glands and a prominent elastic layer that sends fibers into muscle layer to anchor mucosa

16
Q

Describe the submucosa layer of the oropharynx

A

typically not present

17
Q

Describe the muscularis externa layer of the oropharynx:

A

inner circular and out longitudinal layers of skeletal muscle

18
Q

Describe the outermost layer of the oropharynx

A

= adventitia (fibrosa) = tough fibroelastic CT

19
Q

what is the function of the esophagus

A

muscular tube that delivers food and liquid from pharynx to stomach

20
Q

Describe the mucosa layer of the esophagus

A
  1. epithelium = stratified squamous non-keratinized

2. Lamina propria = loose CT + mucosal or cardiac glands present near the ends of esophagus

21
Q

Describe the glands found in mucosa of the esophagus (histology)

A

found in the lamina propria of the mucosa; simple branched tubular glands similar to those in the upper or cardiac region of the stomach

22
Q

Describe the muscularis mucosae in the esophagus

A

single layer of longitudinally oriented SMOOTH muscle

23
Q

what type of tissue is found in the submucosa of the esophagus?

A

coarse collagenous connective tissue (dense irregular) + submucosal glands (esophageal glands proper)

24
Q

Are there any glands found in the submucosa of the esophagus? if yes, describe them

A

compound tubuloalveolar glands with variable distribution;
secrete product to the surface via a duct;
mostly MUCUS, but some serous cells producing lysozyme

25
Q

what is the product of the glands found in the submucosa of the esophagus?

A

mostly mucus, but some serous glands producing lysozyme

26
Q

What are the layers found in the muscularis externa of the esophagus?

A

inner circular layer and outer longitudinal layer

27
Q

what type of muscle is found in the muscularis externa of the esophagus?

A

Upper 1/3 = skeletal muscle; transitions into smooth muscle in the lower 1/3;

this transition reflects voluntary to involuntary swallowing

28
Q

Describe the adventitia (fibrosa) of the esophagus

A

Loose CT that blends with adjacent structures

29
Q

What is the function of the stomach?

A

expanded muscular portion of digestive tube that mixes and partially digests food, producing a pulpy fluid mixture (chyme)

30
Q

what is chyme? where is it produced?

A

mixture of food + gastric juices in the stomach

31
Q

What is the esophagogastric junction?

A

an abrupt change in the eptihelial lining from stratified squamous to simple columnar

32
Q

what type of epithelium is found in the stomach? what is its function?

A

simple columnar; functions in secretions and absortion

33
Q

How are the different regions of the stomach distinguished?

A

via the histology of their mucosal glands

34
Q

Describe the histological characterisitc of the cardia of the stomach

A

has cardiac glands in the mucosal glands

35
Q

Describe the histological characteristic of the body and fundus of the stomach

A

presence of gastric/fundus glands in the mucosa

36
Q

Describe the histological characteristic that defines the pylorus of the stomach

A

pyloric glands

37
Q

What are the 3 major characteristics of the stomach mucosa?

A
  1. Ruga (termporary submucosal folds)
  2. Mammilated gastric areas (thickened mucosal for increased surface area for secretion)
  3. Gastric pits (holes from ruga to gastric pit)
38
Q

What are Rugae? what is their function?

A

temporary longitudinal submucosal folds; serve to accommodate expansion and filling of the stomach

Note: since the submucosa golds, the overlying mucosa temporarily folds as well

39
Q

What are the mamilated/ gastric areas? where are they located?

A

small bulges of the mucosa of the stomach that is thickened;

provide increased surface area for secretion

40
Q

What are gastric pits? where are they found?

A

holes found in the mucosa of the stomach;

the mucosal glands empty into them

41
Q

what type of cells line the surface of the gastric pits? what do they produce?

A

surface mucous cells which produce a thick, cloudy mucus

42
Q

What is the function of the mucos cells that line the gastric pits? (what is the function of the mucus that they secrete?)

A

secrete a thick mucous film that has a high BICARB (HCO3) content and protects the eptihelium from the acidity of the gastric contents

43
Q

Describe the lamina propria of the stomach

A
  1. mucosal glands are each surrounded by loose CT that contains blood vessels, lymphocytes, plasma cells, eosinophils, mast cells, and macrophages
  2. Muscularis mucosae (deep to glands)
44
Q

Describe the muscularis mucosae of the stomach (location, function)

A

located in the lamina propria deep to the mucosal glands;

extends smooth muscle cells up between the glands (contraction of smooth muscle aids in emptying the glands)

45
Q

Are there any glands present in the submucosa of the stomach? if so, describe them

A

No glands present

46
Q

Describe the submucosa of the stomach

A

Dense irregular CT;
NO GLANDS
Nerves and ganglion cells of submucosal (Meissner’s plexus)

47
Q

Describe the Muscularis Externa of the stomach (how many layers/what are they, function)

A

3 layers of SMOOTH muscle: inner oblique, middle circular, outer longitudinal
function: contractions churn and homogenize food as gastric secretions are added

48
Q

where is the myenteric plexus found?

A

between the circular and longitudinal layers of muscularis externa of the stomach

49
Q

Describe the outer tissue layer of the stomach

A

Serosa: CT that is covered with a mesothelium

50
Q

Where are the cardiac glands found? what type of cells do they contain?

A

located in the cardiac region of the stomach; contain primarily mucous cells

51
Q

Where are the gastric glands found? what do they produce? describe the characteristic histology associated with the gastric glands

A

located in the fundus of the stomach;
produce gastric juices;
The fundus/body has a characteristic two-tone staining appearance due to distribution of multiple cell types

52
Q

Where are pyloric glands found? what type of cells do they contain?

A

located in the pyloric region of the stomach; contain primarily mucous cells