Invertebrate review

2. an animals with a backbone
6. soft-bodied invertebrate usually with a shell
10. remaining attached to one place
12. an animal without a backbone
14. vase-shaped body plan, like that of a hydra
16. type of symmetry in which body parts are mirror images of each other
18. joint-footed animal
20. type of symmetry in which body parts are arranged in a circle around a central point

1. change in body form some animals go through as they mature
3. spiny-skinned invertebrate that lives on the ocean bottom
4. structures, like legs or antennae, that grow out from a body
5. circulatory system in which blood is contained in vessels
7. circulatory system in which blood is not in vessels but surrounds organs
8. describing an organism that does not depend on another for food or a place to live
9. thin layer of tissue that secretes a mollusk's shell
11. protective outer covering on arthropods
13. hollow-bodied animal that has singing cells
15. bell-shaped body plan, like that of a jellyfish
17. tongue-like organ in mollusks that works like a file
19. organs that exchange oxygen and carbon dioxide with water