GI HISTOLOGY

Question 1

What are the four layers of the digestive tract wall?

Answer 1

Mucosa: Lining epithelium and smooth muscle.Submucosa: Dense connective tissue with vessels and nerves.Muscularis: Two smooth muscle layers.Adventitia/Serosa: Connective tissue and protective membrane.

Question 2

What is the structure of the esophagus?

Answer 2

Mucosa: Stratified squamous epithelium for protection.Submucosa: Dense tissue with larger vessels.Esophageal glands: Secrete mucus for lubrication.

Question 3

What are the layers of the stomach?

Answer 3

Mucosa: Contains gastric glands.Submucosa: Dense tissue with vessels.Muscularis: Three smooth muscle layers.Serosa: Protective outer layer.

Question 4

What are the types of epithelial cells in the stomach?

Answer 4

Parietal: Secrete HCl and intrinsic factor.Chief: Produce pepsinogen for protein digestion.Mucous: Protect stomach lining.Enteroendocrine: Release hormones for digestion.

Question 5

What is the function of the esophagus?

Answer 5

Conduit between pharynx and stomach.Peristalsis moves food down.

Question 6

What is the histological transition at the gastroesophageal junction?

Answer 6

From stratified squamous to simple columnar epithelium.

Question 7

What is the role of the myenteric plexus?

Answer 7

Regulates peristalsis in the digestive tract.

Question 8

What are the components of the submucosa in the esophagus?

Answer 8

Dense connective tissue with vessels and nerves.Esophageal glands for lubrication.

Question 9

What are the functions of gastric glands?

Answer 9

Secrete gastric juices for digestion.

Question 10

What are the main layers of the esophagus?

Answer 10

Muscularis, adventitia, and mucosa.

Question 11

What are the histological regions of the stomach?

Answer 11

Cardiac, fundus, and pyloric regions.

Question 12

What are the components of the gastric mucosa?

Answer 12

Simple columnar epithelium and gastric glands.

Question 13

What types of cells are found in gastric glands?

Answer 13

Mucous, chief, parietal, enteroendocrine, and stem cells.

Question 14

What is the function of surface mucous cells?

Answer 14

Secrete mucus to protect the epithelium.

Question 15

How do neck mucous cells differ from surface mucous cells?

Answer 15

Less alkaline and more soluble mucus.

Question 16

What is the role of parietal cells?

Answer 16

Secrete HCl and intrinsic factor.

Question 17

What is the structure of fundic glands?

Answer 17

Simple, branched glands for gastric secretion.

Question 18

What is the significance of the adventitia in the esophagus?

Answer 18

Provides structural support and contains vessels.

Question 19

What are the main functions of parietal cells?

Answer 19

Produce HCl and secrete intrinsic factor.

Question 20

What is the role of pepsinogen?

Answer 20

Converted to pepsin for protein digestion.

Question 21

What are the characteristics of chief cells?

Answer 21

Secrete pepsinogen and have a lifespan of 60-90 days.

Question 22

What are the two types of enteroendocrine cells?

Answer 22

Closed: Do not reach the lumen.Open: Exposed to the lumen.

Question 23

How do stem cells contribute to renewal in the stomach?

Answer 23

Produce progenitor cells for epithelial renewal.

Question 24

What distinguishes pyloric glands from fundic glands?

Answer 24

Pyloric glands have deeper pits and more mucus-secreting cells.

Question 25

What are the functions of peptide hormones from enteroendocrine cells?

Answer 25

Regulate metabolism and gastrointestinal motility.

Question 26

What is the significance of the acidic environment in the stomach?

Answer 26

Initiates protein digestion and acts as a bacteriostatic agent.

Question 27

What is the lifespan of chief and enteroendocrine cells?

Answer 27

Both have a lifespan of 60-90 days.

Question 28

What are the main components of the gastric mucosa?

Answer 28

Secretes mucus and contains immune cells.

Question 29

What is the role of the muscularis mucosa?

Answer 29

Aids in secretion and movement of gastric contents.

Question 30

What is the structure of the submucosa in the stomach?

Answer 30

Dense connective tissue with vessels and nerves.

Question 31

Describe the muscularis externa of the stomach.

Answer 31

Three layers of smooth muscle for movement.

Question 32

What is the function of the pyloric sphincter?

Answer 32

Regulates outflow into the duodenum.

Question 33

What is the enteric nervous system?

Answer 33

Innervates smooth muscle and functions independently.

Question 34

What is the epithelial transformation zone at the gastro-esophageal junction?

Answer 34

Transition from squamous to columnar epithelium.

Question 35

What are common diseases of the esophagus?

Answer 35

GERD and Barrett’s esophagus.

Question 36

What is Zollinger-Ellison syndrome?

Answer 36

Excess gastrin secretion causing ulcers.

Question 37

What are the four layers of the GI tract?

Answer 37

Mucosa, submucosa, muscularis, adventitia/serosa.

Question 38

What are the histologic layers of the esophagus?

Answer 38

Mucosa, submucosa, muscularis, adventitia.

Question 39

What are the histologic layers of the gastric wall?

Answer 39

Mucosa, submucosa, muscularis, serosa.

Question 40

What is the structure of gastric pits and glands?

Answer 40

Pits lead to glands that secrete digestive enzymes.

Question 41

What types of cells are found in gastric glands?

Answer 41

Mucus, parietal, chief, enteroendocrine, stem cells.

Question 42

What are some common diseases of the esophagus?

Answer 42

GERD, esophagitis, cancer.

Question 43

What are some common diseases of the stomach?

Answer 43

Gastritis, peptic ulcers, cancer.