| A | B |
| adaptation | any structure or behavior that helps a living thing meet its needs for survival |
| camouflage | any coloring, shape, or pattern that allows a living thing to blend into its surroundings |
| migration | the movement of an animal from one location to another as the seasons change |
| hibernation | a long, deep sleep in which an animal's heart rate and breathing are much slower than normal |
| symbiosis | a special way in which two different kinds of living things live together |
| parasite | a plant or animal that feeds off another living thing and harms it |
| host | a plant or animal that is harmed by a parasite |
| pollution | anything harmful added to the air, land or water |
| recycle | to use the same materials over and over again |
| endangered | having a population of plants or animals that is falling low in number and that is in danger of becoming extinct |
| extinct | no longer existing |
| fossil | any mark or remains of a plant or animal that lived a long time ago |