Structure of the Heart

1. A tiny blood vessel where diffusion can occur
4. In three chambered hearts, oxygenated and deoxygenated blood _____ in the ventricle
6. The type of animal that has a two chambered heart
7. Mammals and ________ have four chambered hearts
9. The chamber of the heart that pumps blood to the lungs
10. The term that describes blood that has a high concentration of oxygen
13. Number of chambers of a human heart
14. The term that describes blood that has a low concentration of oxygen
16. The blood vessel that carries blood from the upper body to the heart
19. Number of chambers of the hearts of reptiles and amphibians
22. The blood vessel that carries blood from the lungs to the heart
24. The muscular organ of the circulatory system which contracts to pump blood around the body
28. The chamber of the heart that pumps blood to the body

2. The chamber of the heart that receives blood from the body
3. The term for the chambers of the heart that PUMP blood
5. The blood vessel that carries blood from the lower body to the heart
8. The side of the heart that pumps deoxygenated blood from the body to the lungs
11. Tubes of the circulatory system through which blood travels
12. A general name for a blood vessel which carries blood AWAY from the heart
15. The blood vessel that carries blood from the heart to the body
17. The blood vessel that carries blood from the heart to the lungs
18. Flaps in the heart that prevent the back flow of blood through the heart
20. A general name for a blood vessel which carries blood TOWARDS the heart
21. The chamber of the heart that receives blood from the lungs
23. The muscular wall that separates the ventricles in a four chambered heart
25. Part of the circulatory system that carries oxygen, glucose and cell waste
26. The term for the chambers of the heart that RECEIVE blood
27. The side of the heart that pumps oxygenated blood from the lungs to the body