| A | B |
|---|
| motion | a change in position compared to the starting location |
| force | energy, such as a push or a pull, that changes the motion or shape of an object |
| speed | the rate of motion |
| gravity | the force that pulls all objects toward the center of Earth |
| friction | the force, or resistance, caused when two things rub together |
| mass | the amount of matter in a substance |
| ecosystem | all the living and nonliving things in an area and their interactions with one another |
| organism | any living thing, including all plants and animals |
| abiotic factors | the part of an ecosystem that is not alive |
| nutrient | a substance that is a needed source of nourishment or nutrition for a plant or an animal |
| producer | an organism that makes its own food as well as food for consumers |
| consumer | an organism that survives by eating other organisms in an ecosystem |
| herbivore | an animals that eats only plants as food |
| carnivore | an animal that eats other animals as food |
| omnivore | a consumer that eats both plants and animals as food |
| decomposer | an organism that breaks down dead matter |
| food chain | the order in which animals feed on plants and on other animals |
| food web | all of the connected and interacting food chains in an ecosystem |
| water cycle | the continuous circulation of water bettwen Earth's surface and the atmosphere |
| evaporate | to change from a liquid into a gas |
| condense | to change from a gas into a liquid |
| precipitation | water that falls to Earth |
| erosion | the wearing away of soil and rock by water, wind or ice |
| valley | a long, low area of land between hills or ranges or hills or mountains |
| floodplain | the low-lying land near a stream or river that is covered by water during times or heavy rain |
| delta | a deposit of sediments where a stream enters a larger, calmer body of water |
| electric current | the movement of electric charges in a conductor |
| battery | a container filled with metal plates and chemicals that react to produce electric current |
| contact | touching each other |
| complete circuit | a complete path that electric current moves through |
| incomplete circuit | a path that electric current is not able to move through because it is incomplete |
| conductor | somethign that transfers heat or electricity |
| insulator | a material that blocks or reduces the flow of heat, electricity, or sound |
| magnet | any material that has a magnetic field around it and so attracts iron and steel |
| attract | to pull toward itself |
| repel | to push away |
| iron | a strong, hard metal that is magnetic |
| pole | one of the two ends of a magnet where the magnetic force is strongest |
