Histology of Alimentary Canal



Histology of human alimentary canal

The wall of the alimentary canal (from the esophagus to rectum) consists four basic layers:
  • Serosa: It is the outer mode layer. Serosa is made up of thin mesothelium (epithelium of visceral organs) with areolar connective tissue.
  • Muscularis: It is composed of smooth muscles usually arranged into an outer longitudinal and inner circular muscle fibre.
  • Submucosa: It is composed of loose connective tissue richly supplied with blood and lymphatic vessels and in some areas with glands.
  • Mucosa: It is the inner most layer which secretes mucus. It is composed of three layers:
  1. Muscularis mucosa- It is a thin layer of smooth muscles.
  2. Lamina propria- It is a layer of connective tissue. It is unusually cellular so it is compared to most connective tissues.
  3. Epithelium- innermost layer and is responsible for most digestive, absorptive, and secretory processes.