| A | B |
|---|
| Mullusk | An invertebrate divided into three parts. |
| Arthropod | A member of the largest group of invertebrates. which includes insects. |
| Molting | The process by which an arthopod sheds its external skeleton. |
| Crustacean | A class of arthropods that includes crabs, lobster, crayfish, and sow bugs. |
| Arachnid | A class of arthropods that includes spiders, scorpions, mites, and ticks. |
| Complete metamorphosis | Changes in form during development in shich earlier stages do not look like the adult. |
| Incomplete metamorphosis | Changes in form during development inshich earlier stages look like the adult. |
| Pupa | A stage in the development of some insects that lead to the adult stage. |
| Tube foot | A small structure used by echinoderms for movement |
