What process allows dietary fats to enter the lymphatic system from intestinal enterocytes?

• A. Absorption into portal blood
• B. Direct diffusion into blood capillaries
• C. Formation of chylomicrons and uptake into lacteals
• D. Conversion to lipoproteins for blood transport

Answer: (C)

Long-chain dietary fats are reassembled inside enterocytes into triglycerides and packed with cholesterol and apolipoproteins into chylomicrons. These large particles are too big to enter the blood capillaries directly, so they are taken up by the lymphatic vessels called lacteals in the intestinal villi. The lymphatic system carries the chylomicrons away from the gut and eventually dumps them into the bloodstream through the thoracic duct. Short- and medium-chain fatty acids, in contrast, can enter portal blood directly, but the typical route for dietary fats is via chylomicron formation and entry into the lacteals.