Echinoderms have a unique water vascular system with tube feet.
Echinoderms have a hydraulic system of locomotion called the water vascular system.
Echinoderms have a hydraulic system of locomotion with tube feet.
How do echinoderms use their feet to locomote themselves?
[A] one at a time
[B] to move people
[C] running and lifting
[D] protein channels
[E] a hydraulic system
[F] it needs them
[G] undulations
[H] It helps them survive