Cilia are microscopic, hair-like structures that project from the surface of certain cells. Their primary function involves synchronized beating motions to propel fluids, mucus, or cells across a surface. For example, in the respiratory tract, these structures sweep mucus containing debris up and out of the lungs.
Understanding the precise structure and function of these cellular components is crucial for diagnosing and treating a range of medical conditions. Dysfunctional activity or absence of these structures can lead to chronic respiratory infections, infertility, and other developmental disorders. Historically, observation and analysis of these structures have evolved from simple microscopic examination to advanced genetic and molecular techniques, leading to a more thorough comprehension of their role in human health.