Eli5: How do scallops have such beautiful, perfectly shaped shells? They’re basically just small globs of meat, right?

Question

Do they find the shells lying around and climb inside them? Do the shells form from sand around their glob bodies over the course of a hundred years?

In: Biology

Answer 1

As mollusks develop in the sea, their mantle tissue absorbs salt and chemicals. They secrete calcium carbonate, which hardens on the outside of their bodies, creating a hard shell.