What are cilia and why are they important?
The respiratory system includes upper respiratory structures (sinuses, ears, nose, pharynx) and lower respiratory structures (lungs containing bronchi, bronchioles, and alveoli, and respiratory muscles). The health of the entire system is managed to a large degree by the interaction of billions of cilia (microscopic hair-like cells) beating debris-laden mucus to the large airways where it can be coughed out. When this system (cilia, mucus, and cough) is working, it keeps the respiratory system clean and functioning. When any one of the three components is ineffective, however, the system gets overwhelmed and chronic inflammation and infection may result.
