Question

cilia are used to move unicellular organisms through watery environments. what role do cilia play in humans?
a) they move debris out of respiratory airways.
b) they protect cells from harmful substances.
c) they expel wastes through the plasma membrane.
d) they hold neighboring cells in a fixed position.

Explanation:

In humans, cilia in the respiratory airways move in coordinated waves to push mucus - containing debris out of the airways, protecting the respiratory system.

Answer:

A. They move debris out of respiratory airways.