Assertion: echinoderm's structure | /r/CapableOf | protrude through the endoskeleton
Facets:
value: for locomotion
type: PURPOSE
Source sentences:
text: Electron microscopy of the surface of a sea urchin demonstrates this elegant arrangement, a sponge-like mesh which creates a plate that allows for special structures to protrude through the endoskeleton for locomotion, feeding, gas exchange, and protection.