What are echinderms?

Answer 1

Echinoderms are invertebrates that have internal skeletons and spines sticking out from their bodies.

Answer 2

Echinoderms are a group of marine animals that include sea stars, sea urchins, and sand dollars. They have spiny skin and a unique water vascular system that helps them move, feed, and respire. Echinoderms are known for their radial symmetry and can be found in oceans around the world.