Circulatory and Respiratory Systems

2. A yellowish fluid that is mostly water in which blood cells are suspended.
3. A sheet-like muscle beneath the lungs that expands and contracts the chest cavity to control breathing.
5. A muscular organ that pumps blood throughout the body. Made of cardiac muscle.
9. A transport system that uses blood to carry nutrients and oxygen to the cells of the body.
11. The body system that takes in oxygen and releases carbon dioxide.
12. The tube that transports air from the throat to the lungs, also called the windpipe.
14. A cell fragment that helps to form blood clots and stop bleeding.
15. A blood cell that carries oxygen to the cells of the body and carries carbon dioxide from cells back to the lungs.
16. Air sacks within the lungs where gases are exchanged between the lungs and the blood.
18. A pair of tubes that branch of the trachea and enter the lungs.

1. The cells of the circulatory system that fight disease by attacking invading microorganisms and making anti bodies to fight infection.
4. The process in cells in which oxygen is combined with food (glucose) to release energy.
6. A blood vessel that carries blood away from the heart.
7. Either upper chamber of the heart.
8. Elastic, sponge-like organs in the chest that are the main organs of the respiratory system.
10. Either lower chamber of the heart.
13. A tiny vessel that connects and artery to a vein and exchanges substances such as gases and nutrients between the blood and the body cells.
17. A blood vessel that carries blood toward the heart.