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How do flatworms move across the bottom using cilia and mucus?
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Locomotion
These birds largely reside in coastal areas of North America, although some populations live in the continent's interior along large rivers.
Small flatworms move across the bottom through a process of ciliary gliding. A dense coat of cilia located on the animal's ventral surface beats in a tailward direction, which propels the organism forward.1
To facilitate this movement, the flatworm secretes a continuous stream of mucus over the surface. This mucus serves two critical functions: it attaches the animal to the substrate and raises its body slightly, providing the necessary clearance for the cilia to beat effectively. Because ciliary forces are relatively weak, this method is primarily used by smaller flatworms; larger species must rely on muscular contractions, such as pedal locomotion, to generate sufficient propulsive force.1