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.
Answer:
When the oxygen atoms of different water molecules come together, they repel. When the hydrogen atoms of different water molecules come together, they repel.
Hope this helps
