Upper gastrointestinal tract: mouth to duodenum

Lower gastrointestinal tract: jejunum to anus

Construction and distribution

Oral organs

Nasopharynx - There is a Eustachian tube pharyngeal opening 1cm behind the inferior turbinate (which regulates middle ear air pressure). There is a deep longitudinal groove behind the round pillow of the Eustachian tube and the posterior pharyngeal wall, which is the pharyngeal recess (a common site for nasopharyngeal cancer)

Oropharynx, hypopharynx

Distribution: neck, chest, abdomen

narrow

The upper and lower openings: cardia, pylorus - the front and back walls - the greater and lesser curvatures: the greater curvature of the stomach, the lesser curvature of the stomach

Distribution: cardia, gastric body, pylorus. The lesser curvature and pylorus of the stomach are the most common sites for ulcers

Stomach wall structure: internal oblique, middle ring, external longitudinal

duodenum

Jejunum and ileum

The difference from other intestines is that it contains colonic bands, colonic pouches, and intestinal fat flaps.

Cecum, appendix (McFarland's point - the junction of the middle and outer 1/3 of the line connecting the umbilicus and the right anterior superior iliac spine)

colon, sigmoid colon

rectum

Anal canal: divided into internal hemorrhoids and external hemorrhoids based on the dentate line

Coronary ligament, deltoid ligament, falciform ligament; left lobe of liver, right lobe of liver, bare area

Secrete bile, participate in substance metabolism, detoxification and phagocytosis