Histology of the GI tract

Question 1

What are the layers present in all layers of the GI

Answer 1

• Mucosa
• Submucosa
• Muscualris propria
• Serosa

Question 2

What are the layers of the mucosa?

Answer 2

• Epithelium
• Lamina propria
• Muscularis mucosal

Question 3

Where are secretory mucosa found

Answer 3

In the stomach

Question 4

Where is absorptive mucosa found?

Answer 4

in the SI

Question 5

Where is absorptive/protective mucosa found?

Answer 5

In the LI

Question 6

What feature is characteristic of the SI

Answer 6

villi and crypts

Question 7

what is the cells are found in the LI

Answer 7

cells which specialise in water absorption and mucous secretion

Question 8

What kind of epithelium is found in the oesophagus?

why?

Answer 8

Stratified squamous non-keratinised

Deals with large clumps of food

Question 9

what type of muscle is found in the muscularis external of the oesophagus

Answer 9

Top 1/3rd: SKELETAL
Middle 1/3rd: SKELETAL AND SMOOTH
Bottom 1/3rd: SMOOTH

Question 10

Why are different types of muscle found in the oesophagus?

Answer 10

Skeletal is used for voluntary control

Smooth is used for in voluntary control

Question 11

What is found in the submucosa of the oesophagus?

Answer 11

Mucosal glands

Question 12

What type of epithelium is found in the stomach?

Answer 12

Simple columnar epithelium

Question 13

What is found in the mucosa of the stomach?

Answer 13

• Lots of glands for digestion- release contents into lamina propria
• Parietal: stain pink as they secrete Hcl
• Chief cells: At base of gland- secrete pepsinogen- a lot darker
• Gastric pits

Question 14

Is there much lamina propria in the stomach?

Answer 14

NO

Question 15

Properties of histology of small intestine

Answer 15

GENERAL:
-Look for villi 
-Look for crypts 
-Look for Peyer's patches 
Duodenum: Brunner's cells 
Jejunum:few of Peyer's patches and fewer Brunner's cells
Ileum:Many Peyer's patches

Question 16

What are Peyer’s Patches?

Answer 16

Collection of lymphoid tissue

Question 17

What type of epithelium is found in the SI?

Answer 17

simple columnar

Question 18

In what layer at Brunner’s glands and peyers patches found?

Answer 18

In the submucosa

Question 19

what is the function of Brunner’s glands?

Answer 19

They coat the intestine with a lining of anti-acid lining

Question 20

What are the large folds which extend into the lumen known as?

Answer 20

Plicae

Question 21

What kind of muscle is found in the muscularis mucosa fo the SI?

Answer 21

smooth

Question 22

what kind of cells are found in the surface epithelium of the SI?

Answer 22

Goblet cells which secrete mucin

Question 23

General feature of LI

Answer 23

• lots of moth like cells- Mucous secreting
• NO VILLI
• thick mucosa

Question 24

What sort of epithelium is found in the rectum?

Answer 24

Stratified squamous

Question 25

What is the name of the plexus between the circular and longitudinal muscle called?

Answer 25

Myenteric

Question 26

What is the name of the plexus in the submucosa

Answer 26

Meissner’s plexus/ submucosal plexus

Question 27

What is the function of the submucosal plexus

Answer 27

Controls the muscularis mucosa

Question 28

what is the function of myenteric plexus

Answer 28

controls muscularis externa

Question 29

What are the 4 different types of mucosa

Answer 29

• Protective: stratified squamous non-keratinised
• Secretory: Lots of glands
• Absorptive: VIlli/ crypts
• Protective/absortive: rectum