NUTR 120 Lecture Notes - Lecture 6: Thoracic Duct, Chylomicron, Low-Density Lipoprotein
Document Summary
How is fat digested and absorbed: triglycerides in food enter the small intestine, bile acids enter small intestine and disperse fat into small droplets (emulsification, lipases (enzymes) break down fat, formation of micelle. Fat attracted to interior and water surrounds exterior: fatty acids + monoglycerides absorbed into mucosal cells (absorption) If the fatty acid is less than or equal to 12 carbons in length it is absorbed into hepatic portal veins to the liver along with sugars, amino acids, etc. If the fatty acid is 14 carbons or more, there will be a reformation of the triglyceride in the mucosal cell, packaged into chylomicron to the lymph system then to the blood system at thoracic duct. Bile acids: summary: made from cholesterol (in liver, required for, emulsification of fat, formation of micelles, amount required each day are much larger than the amount synthesized. Reabsorption and recycling of bile acids is very efficient.
