The serving size must be what is customarily consumed. Foods meeting this criterion may use free of calories, no calories, calorie-free, zero calories, trivial source of calories, without calories, dietarily insignificant source of calories or negligible source of calories on the food label. Video of the Day
Body Symmetry of Phylum Chordata Although chordates come in many shapes and sizes, they share the four characteristics listed above and they also all have bilateral symmetry. If you divide a chordate in half, you will get two equal pieces that are mirror images of each other.
Craniates, one of the three subdivisions of chordates, have distinct skulls-including hagfish, which have no vertebrae. Michael J. Benton comments, craniates are characterized by their heads, just as chordates, or possibly all deuterostomes, are by their tails.t has also proved difficult to produce a detailed classification within the living chordates. Attempts to produce evolutionary  family trees  give results that differ from traditional classes because several of those classes are not monophyletic. As a result, vertebrate classification is in a state of flux.