| A | B |
|---|
| Kingdom | The largest group that an organism is classified into. |
| Fossil | Any evidence of an organism that lived in the past. |
| Cell | The smallest unit that makes up all living things. |
| Extinct | When an organism is no longer |
| tissue | cells that are organized and work together (like the skin). |
| species | the smallest group into which an organism is classified |
| habitat | an organism's home |
| food chain | set of steps in which organisms get food |
| pollution | harmful substances added to Earth's water, air, and land. |
| organ | group of tissues that work together |
| how living things change over time | what can we learn by looking at fossils? |
| bird, insect | the organisms in this food chain are consumers. |
| algae | a living thing that might be found in a drop of pond water |
| chlorophyll | this is found in plant cells but not in animal cells |
| cat | found in the same group of animals as tigers, leopards, cheetahs, and jaguars |
