interior structure of small intestine large intestine

The wall of alimentary canal  (A.C) including small and large intestines possesses 4 layers:

• Rugae − irregular folds formed by mucosa in stomach

• Villi − These are finger-like folding formed by mucosa in small intestine. Cells that line villi bear microscopic projections called microvilli. These increase the surface area.

• Villi have a network of capillaries and lacteal (a large lymph vessel). This helps in absorption of food in small intestine.