| A | B |
|---|
| vertebrate | animal with a backbone |
| invertebrate | animal without a backbone |
| radial symmetry | describes animals with body parts arranged in a circle around a central point, similar to a bicycle wheel |
| bilateral symmetry | describes animals with body parts arranged in the same way on both sides of their body |
| sessile | describes organisms, such as trees, that reman attached to one place during their lifetime |
| filter feeder | an organism that obtains food and oxygen by filtering if from the water in which it lives |
| collar cell | in sponges, the lining cells that help water move through the sponge by the beating of flagella |
| regeneration | the ability of an organism to replace body parts; a type of asexual reproduction in which a whole new organism grows from just a part of the parent organism |
| hermaphrodite | an animal that produces both sperm and egg |
| larva | young organism that develops between egg and adult stages |
| cnidarian | a phylum of hollow-bodied animals with stinging cells |
| tentacle | the armlike structures that surround the mouths of some organisms and help them to capture food |
| polyp | a vase-shaped cnidarian that usually is sessile |
| medusa | a bell-shaped cnidarian that is free-swimming |
| free-living | describes an organism that finds its own food and place to live without depending on another organism, the opposite of parasite |
| anus | an opening at the end of the digestive tract throuogh which solid wastes leave the body |
| cyst | a young parasitic worm with a protective covering |
