Chylomicrons

Definition

Chylomicrons are lipoprotein particles formed in the small intestine that transport dietary lipids through the lymphatic system into the bloodstream. They play a crucial role in lipid digestion and absorption.

5 Must Know Facts For Your Next Test

1. Chylomicrons are composed primarily of triglycerides, with a smaller amount of cholesterol, phospholipids, and proteins.
2. They are synthesized in the enterocytes (intestinal cells) after the absorption of dietary fats.
3. Chylomicrons enter the lymphatic system via lacteals before reaching the bloodstream.
4. Apolipoproteins on chylomicrons help to stabilize these particles and facilitate lipid transport.
5. Once in the bloodstream, enzymes like lipoprotein lipase break down chylomicrons, releasing fatty acids for energy or storage.

Review Questions

• What is the primary function of chylomicrons in lipid digestion?
• Where are chylomicrons synthesized and what pathway do they follow to enter the bloodstream?
• Which enzyme is responsible for breaking down chylomicrons in the blood?

Related terms

Lipoprotein:

Lipoproteins are complexes made up of lipids and proteins that transport fats through the blood and lymphatic fluid.

Triglyceride: Triglycerides are a type of fat (lipid) found in your blood used by your body as an energy source.

Lipoprotein Lipase: An enzyme that breaks down triglycerides in lipoproteins into free fatty acids and glycerol for cellular uptake.