adaptions of villi

• 1st adaption of villi

  finger like shape - large surface area
• 2nd adaption of villi

  single layer of surface cells ( epithelial cells ) ensure small diffusion distance
• 3rd adaption of villi

  epithelial cells further fold to form micro - villi
• 4th adaption of villi

  each villi has rich capillary network allowing the products of digestion to be removed quickly - ensure steep diffusion gradient
• 5th adaption of villi

  glucose and amino acids will enter blood stream.

  products of lipid/fat digestion will enter structure called lacteal in centre of villi