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

Cilia in the respiratory tract play a vital role in maintaining respiratory health by moving mucus out of the airways. The respiratory tract is lined with ciliated epithelial cells that help propel mucus, which traps dust, pathogens, and other particulate matter, toward the throat where it can be swallowed or expelled. This action is part of the mucociliary escalator system, which is crucial for keeping the airways clear and preventing infections or blockages.

While filtering air is an important aspect of respiratory function, it is primarily carried out by nose hairs and mucus rather than by cilia. The cilia do contribute to the overall process of maintaining cleanliness in the airways, but their specific role is in the movement of mucus. Enhancing gas exchange in the alveoli and facilitating oxygen diffusion are functions attributed to the alveolar walls and surrounding capillaries rather than cilia, which are located along the larger airways.