Histology of the GI tract

Question 1

What are the 4 layers/tunics of the gut tube?

Answer 1

Mucosa

Submucosa

Muscularis externa (propria)

Adventitia/serosa

Question 2

Different mucosal layers are adapted for their function

Where would you find protective epithelium?

Answer 2

oral cavity, pharynx, oesophagus, and anal canal

Question 3

Where would you find secretory mucosa?

Answer 3

Stomach

Question 4

Where would you find absorptive/protective epithelium?

Answer 4

Large intestine

Question 5

Where would you find absorptive epithelium?

Answer 5

Small intestine

Question 6

What type of epithelium is found in the oesophagus, anal cavity and mouth?

Answer 6

Stratified squamous

Suited to role as Protective epithelium

Question 7

What layers comprise the Mucosal layer?

Answer 7

• Epithelium
• Lamina propria
• Muscularis mucosae (interna)

Question 8

What is the purpose of the lamina propria?

Answer 8

Layer of loose connective tissue which provides vascular support for the epithelium

It also often contains glands and lymphoid cells

Question 9

What is the muscularis mucosae?

Answer 9

Thin double layer of smooth muscle

Doesn’t do much apart from local movement of the mucosa