ABSORPTION

• PROCESS OF LIPID ABSORPTION?

  1. Liver produces bile
  2. Emulsify large lipid droplets into smaller lipid droplets (larger SA)
  3. Hydrolysed by lipase + water
  4. To produce FAs + MGs
  5. Combine with bile salts
  6. Form micelles
  7. Micelles release MGs and FAs at epithelial cells
  8. Enter cell (simple diffusion)
  9. FAs and MGs recombine = TGs in SER
  10. TGs combine with cholesterol and lipoproteins to form chylomicrons at the GA
  11. Exit cell by exocytosis
  12. Chylomicron enters lacteals
  13. Eventually reaches bloodstream
  14. Triglycerides hydrolysed by enzymes in capillary endothelium to form FAs and glycerol
  15. Diffuse into cells
• WHAT DOES THE LIVER DO IN ABSORPTION OF LIPIDS?

  produce bile (bile salts)
• WHAT ARE MICELLES MADE UP OF?

  fatty acids, monoglycerides and bile salts
• HOW DO MONOGLYCERIDES AND FATTY ACIDS ENTER EPITHELIAL CELL?

  simple diffusion
• WHY CAN FATTY ACIDS AND MONOGLYCERIDES SIMPLY DIFFUSE INTO THE EPITHELIAL CELL?

  dissolve in phospholipid bilayer (lipid-soluble)
• WHERE DO FATTY ACIDS AND MONOGLYCERIDES RECOMBINE?

  smooth endoplasmic reticulum
• WHAT IS A CHYLOMICRON?

  triglyceride, cholesterol, lipoproteins
• WHERE IS A CHYLOMICRON FORMED?

  Golgi Apparatus
• WHAT DO MICELLES DO?

  • increase solubility of fatty acids in water
  • carry fatty acids to epithelial cell
  • maintain higher concentration of fatty acids compared to epithelial cell
• WHAT ARE LACTEALS?

  part of lymphatic system