Answer key

2. hollow muscular organ that pumps the blood through the circulatory system.
5. This is the part that carries oxygenated blood away from the heart and to other parts of the body.
7. the two air tubes that branch off of from the trachea and carry atmospheric air directly into the lungs.
9. blood vessels that form a network between the arterioles and venules.
11. a gelatinous or semisolid mass of coagulated blood.
14. The main organ of the respiratory system
15. the muscular-walled tubes forming part of the circulation system by which blood

1. the nasal passage and other regions of the respiratory tract.
3. This part of the cycle carries oxygen-depleted blood away from the heart
4. circulation This type of circulation provides the heart with oxygenated blood so it can function properly.
6. tubes forming part of the blood circulation system of the body
8. the tiny sac like structure present in the lungs
10. breathing begins with a dome-shaped muscle located at the bottom
12. filters the air we inhale and branches into the bronchi.
13. transport media of nearly everything within the body. It transports hormones, nutrients, oxygen, antibodies, and other important things needed to keep the body healthy.