| A | B |
|---|
| cell membrane | thin living cell covering |
| nucleus | controls activities of other cell parts |
| vacuole | storage sac in a cell |
| cytoplasm | jellylike fluid between cell membrane and nucleus |
| invertebrate | animal with no backbone |
| tentacle | slender, flexible body part used to touch, hold, or move |
| segmented | made up of many smaller sections |
| planarian | flatworm that lives in streams or ponds and eats dead animals or plants |
| parasite | organiosm that harms another organism by living on it and taking nutrients from it |
| earthworm | type of segmented worm |
| regenerate | regrow lost body parts |
| siphon | organ through which mollusks gorce out water causing jet action and propelling them |
| mollusk | invertebrate with an unsegmented soft body, covered by a hard shell |
| crustacean | five pairs of legs, two body segments--crab, lobster, shrimp |
| arachnid | four pairs of legs, two body segments--spider, mite, tick |
| insect | three pairs of legs, three body segments--grasshopper, beetle, butterfly |
| stinging-celled | jellyfish, coral, anemone |
| spiny-skinned | sand dollar, sea urchin, sea star |
| soft-bodied | mollusk, octopus, squid |
| arthropod | has jointed feet and exoskeleton |
| exoskeleton | hard covering that supports the body |
| antennae | feelers on the heads of some arthropods |
| compound eyes | form sharp images and see movement |
| simple eyes | see light and dark |
| thorax | middle section of insect's body |
| abdomen | rear section of insect's body |
| vertebrate | animal with backbone |
| lateral line | row of tiny holes with nerve endings that sense movement |
| amphibian | begins with gills, develops lungs--frogs, salamanders |
| reptile | breathes with lungs, lays eggs with shells--lizards, snakes, crocodiles, turtles |
| mammal | makes milk for young, has hair or fur--raccoons, walruses, kangaroos, whales |
| fish | breathes with gills, has lateral line |
| bird | has feathres, lays eggs with shells |
| cold-blooded | body temperature changes with temperature of air around it |
| warm-blooded | body temperature stays same even when that around it changes |
