Puzzle time

2. The passage that connects the throat to the lungs.
5. Another term for eggs produced in the female reproductive system.
6. The process where a sperm cell and an egg cell combine to form a new organism.
9. The male reproductive cell.
11. The opening in the body through which air enters.
12. conductor, A substance that transfers heat effectively.
13. system, The system responsible for transporting oxygen, nutrients, and other substances throughout the body.
17. Small blood vessels where the exchange of oxygen and carbon dioxide takes place.
20. The organ that pumps blood through the circulatory system.
21. The external part of the nasal cavity that also serves as an entrance for air.
22. exchange, The process by which oxygen is taken in and carbon dioxide is released from the body.
23. The process of changing a solid into a liquid by heating.
25. point, The temperature at which a substance changes from solid to liquid.

1. Materials that allow heat or electricity to pass through them easily.
3. change, A change where the substance can return to its original form.
4. point, The temperature at which a substance changes from liquid to gas.
7. The female reproductive cell.
8. The process of changing a liquid into a gas by heating.
10. conductor, A substance that allows electricity to flow through it.
14. system, The system that helps in the exchange of gases between the body and the environment.
15. The period of physical and emotional changes that occur in adolescents as they mature.
16. The muscle that aids in breathing by moving to allow airflow in and out of the lungs.
18. Blood vessels that carry oxygenated blood away from the heart.
19. Blood vessels that carry deoxygenated blood back to the heart.
24. change A change that results in the formation of a new substance that cannot revert to its original state.