<em>Structure and Function of ArthropodsArthropods range in length from about 1 millimeter to 4 meters (about 13 feet). They have a segmented body with a hard exoskeleton. They also have jointed appendages. The body segments are the head, thorax, and abdomen. </em><span><em> In some arthropods, the head and thorax are joined together as a cephalothorax.</em></span>
Large crystals indicate that it cooled very quickly. If it cooled slowly, it would have time to settle down and make a nice smooth rock.
I believe that the answer is: Most organisms are made up of one or more cells
Cell Theory was first developed in 1839 by Schleiden and Schwann, they stated that all organisms are composed of one or more cells.
