Which type features cilia that move mucus and debris across its surface?

• A. Ciliated epithelium
• B. Columnar epithelium
• C. Compound epithelium
• D. Simple cuboidal epithelium

Answer: (A)

The ability to move mucus and debris across a surface relies on hairlike projections called cilia that beat in coordinated waves. Ciliated epithelium has these cilia on its surface, which propel mucus upward and out of the airways, helping keep the tract clear of particles and pathogens. This is particularly important in the respiratory system, where goblet cells produce mucus and the cilia sweep it toward the throat to be swallowed or expelled.

The other descriptions refer to cell shape or layering rather than the presence of cilia: columnar epithelium describes tall, column-shaped cells; simple cuboidal epithelium is a single layer of cube-shaped cells; compound (stratified) epithelium has multiple layers but isn’t defined by the presence of cilia.