Absorption in the Small Intestine

• Small intestine


  The part of the digestive system where the products of digestion are absorbed into the bloodstream
• Small intestine

  • Very long (around 5 meters in humans)
  • Covered with millions of villi
  • Villi have microvilli that further increase surface area
  • Good blood supply to remove products of digestion
  • Thin membrane under villi for short diffusion path
• Absorption of products of digestion in small intestine

  1. Diffusion of molecules into bloodstream

  2. Active transport for molecules that cannot be absorbed by diffusion
• The features of the small intestine enable a rapid rate of diffusion of the products of digestion into the bloodstream