Across
- 4. Lower parts of the heart, pumping chambers
- 6. Red, iron-rich liquid that is a major component in the circulatory system
- 7. _________ System
- 9. Carry blood away from the heart
- 10. Connect veins and arteries, very tiny
Down
- 1. Relating to Lungs
- 2. Primary organ of the circulatory system
- 3. Donut-shaped artery
- 4. Bring blood back to the heart
- 5. One-way switch; makes sure blood flows one way
- 8. Upper parts of the heart, holding chambers