Large Intestine: Colon Wall (T.S.)

The Principal functions of large intestine are to absorb water and minerals/electrolytes from the remaining undigested material coming from small intestine, therefore the lining epithelium contains absorptive cells and numerous secreting cells (goblet cells) that lubricate the lumen. No digestive enzymes are produced.  

Characteristic Features/ Identification Points:

  • Wall of Colon exhibit temporary folds, which consist of both Mucosa and Sub-mucosa.
  • Villi are absent
  • Lining Epithelium is characterized by Goblet Cells 
  • Intestinal Glands (Crypts of Lieberkühn) 
  • No Glands in Sub-mucosa
  • Muscularis externa of the colon is Atypical, unlike small intestine. The Longitudinal Layer is arranged into strips or bands of smooth muscle called Taeniae Coli (3-bands).
Large Intestine: Colon Histology Transverse Section

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