What is the role of bile acids secreted by the liver as well as lipase and colipase produced by the pancreas?

• A. Digest proteins
• B. Break down carbohydrates
• C. Neutralize stomach acid
• D. Aid in micellar solubilization and absorption of dietary fat

Answer: (D)

The key idea is that fats are digested and absorbed with the help of bile acids and pancreatic enzymes to form micelles that transport fatty acids and monoglycerides to the intestinal lining. Bile acids, secreted by the liver, act as detergents that emulsify dietary fat, increasing surface area and forming mixed micelles with the products of fat digestion. Pancreatic lipase, with the help of colipase, hydrolyzes triglycerides into fatty acids and monoglycerides and remains effective in the presence of bile salts. These micelles are then absorbed by enterocytes in the small intestine.

That’s why the correct choice describes micellar solubilization and absorption of dietary fat. The other options relate to digestion of proteins, carbohydrates, or neutralizing acid, which involve different enzymes or factors.