Question

Mixed micelle of lipids with bile acids and lipid soluble vitamins are absorbed by

• A. Pancreatic lipase
• B. Apolipoproteins
• C. Enterocytes
• D. Chylomicrons

Answer 1

The Correct Option is C

To answer the question regarding the absorption of mixed micelles of lipids with bile acids and lipid-soluble vitamins, we need to understand the process of lipid absorption in the digestive system.

1. Formation of Micelles: In the small intestine, lipids such as triglycerides, phospholipids, and cholesterol are emulsified by bile salts secreted by the liver. This emulsification process breaks down large lipid droplets into smaller ones, facilitating the formation of micelles.
2. Role of Micelles: These micelles comprise bile salts, fatty acids, monoglycerides, cholesterol, and lipid-soluble vitamins such as A, D, E, and K. The micelles serve to transport these molecules closer to the intestinal epithelium for absorption.
3. Absorption by Enterocytes: Enterocytes, which are epithelial cells lining the small intestine, absorb the lipids and vitamins from the micelles. The hydrophobic contents of the micelles are released at the brush border membrane of the enterocytes and then absorbed.
4. Conclusion: The correct answer is Enterocytes, as they are directly involved in taking up lipids and lipid-soluble vitamins from micelles for subsequent transport into the bloodstream and lymphatic system.
5. Explanation of Other Options:
   • Pancreatic Lipase: This enzyme is crucial for the breakdown of triglycerides into free fatty acids and monoglycerides but is not directly involved in the absorption process.
   • Apolipoproteins: These are protein components of lipoproteins involved in lipid transport in the bloodstream, but they do not absorb lipids from micelles.
   • Chylomicrons: These are lipoprotein particles that transport lipids from the intestinal cells into the lymphatic system and blood, but they are formed after enterocytes absorb the lipids.