Layers Of The Gut

Question 1

Name the 4 layers

Answer 1

Mucosa
Submucosa
External muscle layers
Serosa

Question 2

Functions of the mucosa

Answer 2

Facilitate transport and digestion of food

Promote absorption

Produce hormones

Produce mucus

Question 3

Functions of the lamina propria

Answer 3

Produce antibodies - mainly IgA

Protect against bacterial/viral invasion

Question 4

Characteristics of the epithelial layer

Answer 4

Selectively permeable barrier

Question 5

Characteristics of lamina propria

Answer 5

Lots of lymphoid nodules and macrophages

Question 6

Which epithelia is present in the GI system

Answer 6

Stratified squamous in oesophagus and distal anus

Everything else is simple columnar

Question 7

Characteristics of the Muscularis mucosae

Answer 7

Layers of smooth muscle orientated in different directions

Question 8

Functions of the muscularis mucosae

Answer 8

Keeps epithelium in contact with the gut contents

Helps keep the crypt contents dynamic

Question 9

characteristics of the Submucosa

Answer 9

Contains dense connective tissue, blood vessels, glands and lymphoid tissue

Contains submucosal plexus

Question 10

Layers of External muscle layers

Answer 10

Inner circular muscle

Myenteric plexus

Outer longitudinal muscle

Question 11

Contents in the serosa

Answer 11

Blood vessels

Lymph vessels

Adipose tissue

Question 12

Characteristics of the serosa

Answer 12

Continuous with the mesenteries