sea urchin
I think it is the sea urchin although i might be wrong. - you are correct, a sea urchin is in the Echinodermata phylum as the sea star.
Yes, sea stars are able to move the spines in order to protect themselves as armor.
A sea star protects itself by using the sharp spines on its back to attack its predator. :-B
A star fish protects its self by these things they have called shape spines
The sea urchin is a member of the phylum Echinodermataand is covered with spines that may or may not be poisonous.
Class Holothuroidea (sea cucumbers)
So that the sea urchin can protect itself from is enemies, it also has venomous spines. They also use their spines to kill other sea ceatures, so they can eat them.
They have soft spines that look like warts
No, but a relative, the sea cucumber can.
Yes, the uric acid decomposes the calcium structure the spines.
The spines on the oral surface are softer and bend to cover the mouth of the starfish as well as the ambulacral grooves. They are basically for protection.
So that the sea urchin can protect itself from is enemies, it also has venomous spines. They also use their spines to kill other sea ceatures, so they can eat them.