Science Crossword

5. Release of harmful materials into the environment
6. materials found in nature that are used by living things
9. a stiff wall that brings earthquake resistance to a building's structure
11. a wall of earth built to prevent a river from flooding its banks
12. Those parts on the outside of a body or structure
13. A situation in which two objects collide and exchange energy and momentum
14. The area subject to flooding
15. the goal to avoid extinction
17. A machine that converts mechanical energy into electrical energy
19. A barrier constructed to prevent waves from reaching the area behind the wall. Its purpose is to defend property from the force of breaking waves.

1. external skeleton; tough external covering that protects and supports the body of many invertebrates
2. A mechanism to isolate a structure from earthquake shaking in the ground; often flexible pads between a building and the ground.
3. Structures found on the inside of living things, such as the heart, lungs or brain.
4. a device used to capture light energy from the Sun and convert it into electrical energy
7. A device with blades that can be turned by water, wind, or steam that turns a generator in an electricity-producing plant
8. a signal to which an organism responds
10. a path for an electrical current to flow around
16. the sense organ or cells that receive stimuli from within and outside the body
18. claw of an animal, especially a bird of prey