Corey A. Krantz, ale 11, of Youngstown, Ohio, for his question:

What is a turtle shell made of?

Old Pokey's shell is made of bony material, covered with a layer of horny plates. Actually it is an amazing extension of his bony skeleton. The top part is called the carapace and it is fused to the bones of his spine and ribs. The underside is called the plastron and it is built around the breast bone. Hence, the whole shell is part and parcel of his skeletal material. The scales on its surfaces are related to horny fish scales and to the horny hair cells of other animals.

A turtle can poke his leathery neck and legs outside his shell. But this is the limit. He cannot walk right out of his shell and survive. It is a built in part of his body that grows as he grows. Daubing his back with paint causes permanent deformity. So, if you get a Christmas turtle with paint on his shell, take him to an expert who knows the delicate skills needed to remove it safely. A veternarian can perform the operation and sometimes a person at the pet store can solve the problem