Cilia are short, hair-like structures that protrude from the surface of some cells. They are responsible for moving fluids and particles past the cell.

Here's a breakdown:

* Cilia are numerous, short, hair-like structures.

* Flagella are longer, whip-like structures, usually only one or a few per cell.

* Both cilia and flagella are involved in movement, but they differ in their size and structure.

Let me know if you have more questions about cells or any other topic!