Ans.A. Chylomicrons transport dietary TGs and cholesterol from within enterocytes through the lymphatics into the circulation and finally to adipose and muscle tissue for energy use or storage. Cholesterol rich chylomicron remnants then circulate back to the liver for degradation and uptake of their core constituents.
- 95% of dietary lipids are triglycerides. Dietary triglycerides are digested in the stomach and duodenum into monoglycerides and free fatty acids by gastric lipase, emulsification from vigorous stomach peristalsis and pancreatic lipase.
- Dietary cholesterol esters are di esterified into free cholesterol by these same mechanisms.
- Monoglycerides, free fatty acids, and free cholesterol are then solubilized in the intestine by bile acid micelles which shuttle them to the intestinal villi for absorption.
- Once absorbed into the enterocyte, they are reassembled into triglycerides and packaged with cholesterol into chylomicrons the largest lipoproteins.