The GI tract is composed of four main layers, each with distinct histological characteristics:
Mucosa: The innermost layer, consisting of an epithelial lining, lamina propria, and muscularis mucosae. Submucosa: A connective tissue layer containing blood vessels, lymphatics, and nerves. Muscularis externa: Composed of an inner circular and an outer longitudinal muscle layer, responsible for peristalsis. Serosa or Adventitia: The outermost layer, a serous membrane or connective tissue layer depending on the organ's location.
