What is the primary function of cilia in the respiratory system?

What is the primary function of cilia in the respiratory system?

• A. Protect the lungs from infection
• B. Move mucus toward the throat
• C. Filter particles from air
• D. Facilitate gas exchange

Answer: (B)

Cilia play a crucial role in maintaining the overall health and function of the respiratory system, with their primary function being to move mucus toward the throat. These tiny, hair-like structures line the respiratory tract and beat in a coordinated manner to propel mucus, which traps inhaled particles, pathogens, and other debris, upward to the throat. This movement is essential for clearing the airway, allowing for the removal of potentially harmful substances and maintaining a clear passage for air.

By transporting mucus to the throat, cilia help ensure that any trapped particles can be swallowed or expelled from the body, thereby protecting the lungs and facilitating normal respiratory function. This mechanism is part of the body’s defense system, which works continuously to keep the respiratory tract free of obstructions and contaminants.