Question

Compare and contrast the wall of the GI tract in the following regions: mouth, esophagus, stomach, small intestine, and large intestine. How does the wall change throughout the course of the body? Be specific. What additional cells and glands are present in each section and what do they do? Be specific.

Answer 1

Dear Student,

Mouth:

- lines by Keratinized stratified squamous epithelium as this area is subjected to high abrasion.

- used for intake of food

- Tongue has specialized papillae for taste sensation

Oesophagus:

- It is a muscular tube with inner circular and outer longitudinal muscles for facilitating the primary function of transportation of food bolus between the compartments

-It has a length of 25 cms

Stomach:

-Most of the gastric glands are located here.

- The inner surface of the stomach is contacted into many longitudinal structures called Rugae.

-This allows the stomach to stretch and enhance when the food enters.

Small intestine :

Composed of duodenum, jejunum, ileum.

It is compressed into numerous folds and occupy a major portion of the abdominal cavity

Main function is digestion and absorption of nutrients.

The lining has numerous folds known as plicae circulares with numerous villi and microvilli for increasing the surface area for absorption.

Large intestine:

Comprises of caecum,colon and rectum

Rectum has thick band of muscles for the control of passage of faeces.

Numerous goblet cells are present.

Hope you are clear.

?