| A | B |
|---|
| Blastula | hollow ball of cells |
| Bilateral Symmetry | two axis of orientation |
| Ectoderm | outside germ layer, becomes skin |
| Endoderm | inside germ layer, becomes internal organ |
| Mesoderm | middle germ layer, becomes muscle |
| Acoelomate | organism with no body cavity |
| Pseudocoelomate | organism with hollow body cavity |
| Coelmate | organism with fluid filled body cavity |
| Osculum | large opening in the sponge for |
| nematocytes | stinging thread used by cnidaria |
| choanocytes | colar cells used by sponge for feeding |
| Chelicerae | pincers or fangs in Chelicerates |
