| A | B |
|---|
| invertebrate | an animal with no backbone |
| vertebrate | an animal with a backbone |
| tentacle | a slender, flexible body part used to touch, hold, or move |
| segmented | made up of many similar sections |
| parasite | an organism that harms another organism by living on or in it and taking nutrients from it |
| regenerate | regrow lost body parts |
| mollusk | an invertebrate with an unsegmented soft body, often covered by a hard shell |
| arthropod | an invertebrate with jointed feet and a segmented body |
| exoskeleton | a hard covering that supports the body |
| crustacean | an arthropod with five pairs of legs, two pairs of antennae, and two main body segments |
| arachnid | an arthropod with four pairs of walking legs, no antennae, and two body segments |
| thorax | the middle section of an insect's body |
| abdomen | the rear section of an insect's body |
| lateral line | a row of tiny holes with nerve endings that feel changes in water pressure |
| amphibian | a vertebrate that begins life with gills and later develops lungs |
| antennae | feelers on the heads of arthropods |
