Which cellular structure, commonly observed on the apical surface of respiratory epithelium, helps move mucus?

Which cellular structure, commonly observed on the apical surface of respiratory epithelium, helps move mucus?

• A. Goblet cells
• B. Cilia
• C. Microvilli
• D. Nucleus

Answer: (B)

Motile cilia on the apical surface of respiratory epithelium drive the movement of mucus. These hair-like projections beat in a coordinated wave, propelling the mucus layer (which traps dust, debris, and microbes) toward the pharynx to be swallowed or expelled. Goblet cells produce mucus but don’t move it themselves; microvilli increase surface area and aren’t involved in propulsion; the nucleus is simply the cell’s genetic control center. So the structure that moves mucus is the cilia.

Motile cilia on the apical surface of respiratory epithelium drive the movement of mucus. These hair-like projections beat in a coordinated wave, propelling the mucus layer (which traps dust, debris, and microbes) toward the pharynx to be swallowed or expelled. Goblet cells produce mucus but don’t move it themselves; microvilli increase surface area and aren’t involved in propulsion; the nucleus is simply the cell’s genetic control center. So the structure that moves mucus is the cilia.