GI Histology

Question 1

What are functions of the digestive system?

Answer 1

• Swallow and digest food: ingest food and water
• Absorb the water and nutrivitive substances
• Expel solid wastes
• Secretion
• Barrier
• Immunologic protection

Question 2

Functions of the oral cavity

Answer 2

• Receives food
• Chews food
• Moistens food
• Enzymes begin the digestion process (processing of food in the mouth)

Question 3

What type of epithelium predominates in the lining mucosa?

Answer 3

nonkeratinized stratified squamous epithelium

Question 4

What type of epithelium is masticatory mucosa?

Answer 4

epithelium is keratinized stratifiedsquamousepithelium, resist abrasion

Question 5

What type of epithelium is specialized mucosa?

Answer 5

nonkeratinized stratified squamous epithelium possesses taste buds

Question 6

Lips are divided into what?

Answer 6

• External region
• Vermillion zone
• Internal mucosal region

Question 7

What is the external skin region of the lip made of?

Answer 7

Stratified squamous keratinized epithelium

Question 8

What is the vermillion zone made of?

Answer 8

Stratified squamous slightly keratinized epithelium

Question 9

What ist he internal mucosal region made of?

Answer 9

stratified squamous nonkeratinized epithelium

Question 10

Does the vermillion zone have glands?

Answer 10

No- so it requires periodic moistening to prevent desiccation

Question 11

What imparts the pink color of the vemillion zone?

Answer 11

The underlying CT is very rich in sensory innervation and capillaries

Question 12

Hard palate: Keratinized stratified squamous epi is supported by what?

Answer 12

A lamina propria

Question 13

Upper layers of the hard palate are supported by

Answer 13

spicular bone

Question 14

The soft palate has a nasal and oral surface and is involved in the process of

Answer 14

talking, breathing and swallowing

Question 15

Soft palate is supported by what?

Answer 15

skeletal muscle

Question 16

Soft palate houses many

Answer 16

secretory mucous glands

Question 17

What is the nasal surface of the soft palate lined by?

Answer 17

Pseudostratified ciliated columnar epithelium with numerous mixed glands

Question 18

What is the oral surface of the soft palate lined by?

Answer 18

a nonkeratinized stratified squamous epithelium of the wet kind which interdigitated with the underlying lamina propria

Question 19

From esophagus down to wall of GI, it is composed of what layers?

Answer 19

• Mucosa
• Submucosa
• Muscularis externa
• Adventitia or serosa

Question 20

Mucosa of espophagus to GI

Answer 20

• Lined with epi
• Lamina propria (CT)
• Muscularis mucosae (smooth muscle)

Question 21

Submucosa of esophagus to GI

Answer 21

glands, vessels with nerve plexus

Question 22

Muscularis externa of esophagus to GI

Answer 22

• Inner circular, outer longitudinal layers of smooth muscle
• Nerve plexus in between

Question 23

Esophagus- Lumen is lined by

Answer 23

thick protective non-keratinized stratified squamous epithelium and a thin layer of connective tissue, the lamina propria

Question 24

What underlays the lamina propria of the esophagus?

Answer 24

Muscularis mucosa

Question 25

Describe the submucosa of esophagus

Answer 25

very loose, has a fair amount of elastic fibers and contains seromucous glands.

Question 26

Where would you find the peripheral ganglia on esophagus histology?

Answer 26

In the submucosa and between the layers of the muscularis external

Question 27

What is Barrett esophagus?

Answer 27

Intestinal metaplasia of the distal esophagus - patches of red, velvety mucosa extending upward from the gastroesophageal junction

Question 28

Barrett esophagus has increased risk of what?

Answer 28

Esophageal adenocarcinoma

Question 29

What is the cardiac region of stomach?

Answer 29

Superior opening or inlet of the stomach

Question 30

What is the fundus and body of the stomach?

Answer 30

Major part of stomach between fundus and pyloric antrum (has a lesser curvature and greater curvature_

Question 31

What is the pyloric part of the stomach?

Answer 31

Funnel shaped outflow region of the stomach

Question 32

Functions of the stomach

Answer 32

Mechanically churns food and generates a pulp-like fluid called chyme.

Question 33

What absorption occurs in the stomach?

Answer 33

Water, ions, alcohol, aspirin, caffeine

Question 34

Histology of cardiac part of stomach

Answer 34

The length of the pits are ~ equal to the length of the glands Highly coiled glands

Question 35

Histology of fundus of stoamch

Answer 35

Display shorter pits and longer glands

Question 36

Histology of pyloric part of stomach

Answer 36

Deep pits and short coiled glands

Question 37

Epithelial cells: Gastric pits and the new ridges between them are lined by

Answer 37

simple tall columnar epithelium

Question 38

What are enteroendocrine cells?

Answer 38

Peptide-producing and secreting cells that are identified based on reactiont o stains

Question 39

What are enteroendocrine cells involved in?

Answer 39

Coordination of GI function. Receive and send signals

Question 40

Where are enteroendocrine cells found?

Answer 40

At the bases of the glands between other epithelial cells

Question 41

Function fo GI tract regulated by

Answer 41

GI hormones and neuroedocrine mediators produced by neurons

Question 42

Gastrin major location

Answer 42

Pylorus

Question 43

Secretin major location

Answer 43

SI

Question 44

CCK major location

Answer 44

SI

Question 45

GIP major location

Answer 45

Duodenum and jejunum

Question 46

Serotonin major location

Answer 46

stomach, intestines

Question 47

Histamine major location

Answer 47

Mucosa throughout GI

Question 48

Somatostatin major location

Answer 48

Pylorus, duodenum and pancreatic islets

Question 49

Gastin stimulates

Answer 49

Gastric acid secretion, peprisogen, increase motility

Question 50

Secretin stimulates

Answer 50

pancreatic enzyme secretion, pancreatic bicarbonate ion secretion

Question 51

Secretin inhibits

Answer 51

Gastric acid secretion, stomach emptying

Question 52

CCK stimulates

Answer 52

Pancreatic enzyme secretion, gallbladder contraction

Question 53

CCK inhibits

Answer 53

Gastric acid secretion, stomach emptying

Question 54

GIP stimulates

Answer 54

Insulin release

Question 55

GIp inhibits

Answer 55

Gastric acid secretion

Question 56

Serotonin stimulates

Answer 56

increased gut motility

Question 57

Histamine stimulates

Answer 57

Gastric acid secretion

Question 58

Somatostatin inhibits

Answer 58

Gastrin release, gastric acid secretion, release of other GI hormones

Question 59

What are chief cells?

Answer 59

Simple cuboidal cells that line lower part of gastric glands

Question 60

Chief cells are filled with what?

Answer 60

Coarse granules which contain pepsinogen (precurosor to pepsin)

Question 61

What do parietal cells do?

Answer 61

Secrete intrinsic factor and hydrochloric acid

Question 62

Where are parietal cells

Answer 62

Mainly in upper half of glands and sometimes in the base

Question 63

What do parietal cells have a lot of?

Answer 63

Mitochondria and secretory canaliculi

Question 64

At the basolateral memrane of parietal cells, it has receptors for what?

Answer 64

Histamine, gastrin and acetylcholine

Question 65

What stimulates parietal cells to secrete HCL?

Answer 65

Parasympathetic (vagus nerve) mediator acetylcholine

Question 66

What increases secretion of HCL, pepsinoge and icnreases motility?

Answer 66

Gastrin

Question 67

Fenestrated capillaries around the gastric glands facilitate

Answer 67

bicarbonate delivery to protect the surface epithelial cells.

Question 68

Peptic ulcer disease (PUD) most often is associated with

Answer 68

H. pylori infection or NSAID use