A: According to BBC, an endoskeleton is a bone structure located in the interior of an animal, and an exoskeleton is a bone structure located on the exterior of an animal. Each type of skeleton has unique advantages and disadvantages in helping the animal survive.
Minerals made of only one element are called NATIVE minerals (i.e., silver, gold, mercury, copper). Minerals composed of compounds are simply referred to as minerals (i.e., quartz, which is made up on silicon and oxygen).
Native elements are minerals that contain only atoms of one type of element. The elements are not combined with other elements. In nature most elements are combined with other elements to form chemical compounds. So, the native elements mineral group contains a relatively small number of minerals. One mineral contains the elements zinc, carbon, and oxygen. 2  The other mineral contains the elements zinc, silicon, oxygen, and hydrogen. 3  Your friend tells you that the minerals are in the same mineral group.