Microorganisms that move using hairlike projections are called?

The hairlike projections on the external surface of microorganisms is called cilium or flagellum. Their primary role is locomotion of the microorganism, but some of them can also act as sensory organelle. Thus, microorganisms that move using such hairlike surface projections are called ciliates or flagellates.

Cilia and flagella are structurally different, though similar in functions. Cilia is present only on eukaryotic cells, while both the eukaryotes and prokaryotes have flagella. A cell may have...

The hairlike projections on the external surface of microorganisms is called cilium or flagellum. Their primary role is locomotion of the microorganism, but some of them can also act as sensory organelle. Thus, microorganisms that move using such hairlike surface projections are called ciliates or flagellates.

Cilia and flagella are structurally different, though similar in functions. Cilia is present only on eukaryotic cells, while both the eukaryotes and prokaryotes have flagella. A cell may have only a few very flagella, which are long and move in whip-like motion, very slowly. Eukaryotes have a large number (few hundreds) of small cilia on their surface. Cilia rotate and move very rapidly. Many researchers tend to reserve the term flagella to bacteria, while using cilia for eukaryotes. 

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