Micelle

Definition

A micelle is an aggregate of surfactant molecules dispersed in a liquid colloid, forming a spherical structure. In aqueous solutions, the hydrophobic tails face inward while the hydrophilic heads face outward.

5 Must Know Facts For Your Next Test

1. Micelles are formed when the concentration of surfactant exceeds the critical micelle concentration (CMC).
2. In biological systems, micelles facilitate the absorption of lipids and fat-soluble vitamins in the intestines.
3. Micelles play a crucial role in emulsification, aiding in the digestion and transport of lipids.
4. Bile salts form micelles to solubilize cholesterol and other lipids for excretion or absorption.
5. The size and shape of micelles can vary depending on the type and concentration of surfactant molecules.

Review Questions

• What is the critical micelle concentration (CMC) and why is it important?
• How do micelles aid in lipid digestion and absorption in biological systems?
• What roles do bile salts play in the formation and function of micelles?

Related terms

Surfactant: A substance that reduces surface tension between two liquids or a liquid and a solid.

Emulsification: The process of mixing two immiscible liquids to form a stable dispersion.

Bile Salts: Molecules produced by the liver that aid in digestion by emulsifying fats into smaller droplets.