Absorption

• Digested food is now in a soluble form and ready to be absorbed into the bloodstream
• Most absorption of digested food occurs in the small intestine
• The small intestine is structurally adapted for maximum absorption

  • The length ensures that food remains for long periods, allowing time for maximum absorption
  • There are transverse folds and millions of villi in the mucosa of the wall of the small intestine, which increase the absorption surface considerably
• The soluble nutrients are mainly absorbed through the villi
• The villus is structurally adapted for efficient absorption of nutrients

  • the columnar epithelial surrounding the villus is only one cell layer think for fast and easy diffusion
  • Villus is richly supplied with capillaries for the absorption of nutrients
  • Villus has a central lacteal for absorption of fats
  • Goblet cells secrete mucus which is the medium in which nutrients can dissolve
  • The columnar epithelium has many mitochondria which provide energy for active transport
  • Microvilli increase absorption surface