Question

L. short hair like projection that produces movement in some types of cells

Answer 1

The structure you are describing is likely a "cilia" (plural of cilium). Cilia are short, hair-like projections on the surface of some eukaryotic cells. They are composed of microtubules and can beat in coordinated patterns to create movement. Cilia are found in various types of cells, including those in the respiratory tract, where they help sweep mucus and debris out of the airways, and in certain unicellular organisms, where they can aid in locomotion.