Respuesta :

krazecat

Answer:

Endoskeleton

Explanation:

An internal skeleton is called an endoskeleton, which is what vertebrates have.  A sponge endoskeleton consists of short, sharp rods called spicules

Spicules are made of silica, calcium carbonate, etc.

savannahbenenhaley
endoskelton jsgsgwunwbdvdywhwnnddj