What term describes hairlike extensions that help to sweep away fluids and particles from cells?

The correct term for hairlike extensions that help to sweep away fluids and particles from cells is cilia. Cilia are tiny, hair-like structures that protrude from the surface of many types of cells. They are capable of coordinated, wave-like movements, which allow them to move fluids, mucus, and other particles across the surface of the cell. This functionality is particularly important in systems such as the respiratory tract, where cilia help to clear mucus and debris from the airways, thereby maintaining respiratory health and preventing infection.

Flagella, while also hairlike extensions, serve a different purpose, primarily involved in locomotion for single-celled organisms. Pseudopodia are temporary projections of eukaryotic cells used for movement and feeding, allowing the cell to engulf food particles. Fimbriae are short, threadlike structures that bacteria use to adhere to surfaces and do not function in fluid movement. Hence, cilia is the most appropriate term when discussing the mechanism of sweeping away fluids and particles from cells.