Question

Describe the digestion and absorption and vascular transport of a fat (triacylglycerol). Include/specify all relevant mechanical and chemical digestion mechanisms. Identify specific locations, mechanisms and processes – as well as accessory organ contributions. Explain how specific digestive tract structures and components of other systems play a role in digestion, absorption and transport of this nutrient.

Answer 1

Fats, also called as lipids are digested by following mechanism-

Lipids are digested by lipolytic enzymes

Saliva has lingual lipase which digest triglycerides into fatty acid and diacrylglycerol.

In stomach, gastric lipase and tributyrase digest triglycerides into fatty acid and glycerol.

In small intestine, lipids are digested with the help of bile salts, pancreatic lipolytic enzymes and intestinal lipases.

All these digest different lipids and final products formed are fatty acid, cholesterol and monoglycerides.

Now,

Monoglycerides,fatty acids and cholesterol form the miscelle and enter the cells of intestinal mucosa by simple diffusion.

Triglycerides and cholesterol gets esterified and are coated with layer of protein, cholesterol and phospholipid to form chylomicrons.

Chylomicrons enters the lymph vessels and then are transfered into blood from lymph. This happens because chylomicrons cannot enters blood directly

In this way, lymphatic system helps in absorption of fats.