GI Histology - Week 3

Question 1

What kind of epithelium is found in the mouth, laryngopharynx & oropharynx?

Answer 1

stratified squamous epithelium which is generally not keratinized

Question 2

Which kind of epithelium covers the tongue?

Answer 2

Stratified squamous epithelium

Question 3

Which papillae have taste buds on them?

Answer 3

Fungiform
Circumvallate
Foliate

Question 4

Which papillae cover the tongue?

Answer 4

Filliform

Question 5

How are the anterior and posterior tongue structurally different?

Answer 5

Posterior tongue has lymphoid aggregates in submucosa

Question 6

From the oesophagus to the anal canal the architecture of the digestive tract is composed of 4 major layers:

Answer 6

Mucosa, submucosa, muscularis externa, serosa/adventitia

Question 7

What are the 3 layers of mucosa?

Answer 7

Epithelium, lamina propria, muscularis mucosae

Question 8

What are the 2 layers of muscularis externa?

Answer 8

an inner circular layer and an outer longitudinal layer

Question 9

What change occurs at the Gastro-oesophageal Junction?

Answer 9

Abrupt transition from stratified squamous epithelium of oesophagus to the columnar epithelium of the cardia of the stomach

Question 10

What are found at the bottom of gastric pits?

Answer 10

Gastric glands

Question 11

What is the role of chief gastric cells?

Answer 11

Digestive enzyme secreting cell

Question 12

What is the role of the parietal cell?

Answer 12

Produces HCl

Question 13

Where are the gastric pits at their deepest?

Answer 13

Cardia and pylorus

Question 14

How is the structure of the stomach different?

Answer 14

Has an oblique muscle in the muscularis externa to jelp with churning

Question 15

What changes are apparent at the Gastroduodenal Junction?

Answer 15

The inner, circular layer of smooth muscle is markedly thickened to form the pyloric sphincter

Question 16

Between the bases of adjacent villi are pits ‘drilling’ downwards called…

Answer 16

the crypts of Lieberkuhn

Question 17

Which glands are found in the submucosa of the duodenum?

Answer 17

Brunner’s glands

Question 18

Where are the villi at their greatest height?

Answer 18

Jejenum

Question 19

Where are Peyer’s patches primarily found?

Answer 19

Submucosa of the ileum

Question 20

What is the role of goblet cells in the small intestine?

Answer 20

Produce mucin to protect epithelium and lubricate passage of material

Question 21

Where are paneth cells found?

Answer 21

base of the crypts of Lieberkuhn

Question 22

What are the roles of paneth cells?

Answer 22

a defensive function and have a role in regulating bacterial flora

Question 23

What is the role of neuroendocrine cells?

Answer 23

Produce hormones that contribute to the control of secretion and motility (e.g. gastrin, cholecystokinin (CCK), vasoactive intestinal peptide (VIP))

Question 24

Where are stem cells found in the small intestine?

Answer 24

Found at the base of the crypts of Lieberkuhn

Question 25

What is the role of stem cells in the small intestine?

Answer 25

divide to replenish epithelium

Question 26

What is the role of Brunner’s glands in the duodenum?

Answer 26

when stimulated by the presence of chyme they produce a thin, alkaline mucous to neutralise the chyme

Question 27

What are the 2 main cell types in the large intestine?

Answer 27

Absorptive cells and goblet cells

Question 28

What is the purpose of absorptive cells in the large intestine?

Answer 28

For removal of salts and thereby water

Question 29

The outer longitudinal layer of muscularis externa in the large intestine is found in 3 layers called…

Answer 29

teniae coli.

Question 30

What change occurs at the Rectoanal Junction?

Answer 30

anal canal is then continuous with the stratified squamous epithelium of the surrounding skin

Question 31

Which plexus regulates gut motility?

Answer 31

Myenteric plexus between 2 layers of muscularis externa

Question 32

Which plexus regulates the muscularis mucosae?

Answer 32

Submucosal plexus