Surfactant

Definition

Surfactants are compounds that reduce the surface tension of liquids, aiding in the disruption of microbial cell membranes. In microbiology, they play a crucial role in the body's innate nonspecific host defenses by preventing pathogen adherence and promoting clearance.

5 Must Know Facts For Your Next Test

1. Surfactants are produced by epithelial cells in various organs such as the lungs and gastrointestinal tract.
2. They help to trap and remove pathogens from mucosal surfaces through mechanical actions like coughing or ciliary movement.
3. Surfactants can disrupt the lipid bilayers of microbial cell membranes, leading to cell lysis.
4. Pulmonary surfactant specifically reduces surface tension in the alveoli, preventing lung collapse and facilitating gas exchange.
5. Bile salts in the gastrointestinal tract act as surfactants to emulsify fats and disrupt bacterial membranes.

Review Questions

• What is the primary function of surfactants in innate nonspecific host defenses?
• How do surfactants contribute to pathogen clearance in the respiratory system?
• In which organ systems are surfactants particularly important for preventing microbial infections?

Related terms

Epithelial Cells: Cells that line the surfaces of organs and structures throughout the body, playing a key role in barrier function.

Mucociliary Escalator:

A mechanism involving mucus and cilia that traps and moves particles out of the respiratory tract.

Bile Salts: Compounds produced by the liver that emulsify fats during digestion and have antimicrobial properties.