GRADE 6 Circulatory and Lymphatic Systems Study Guide 1. Which organ pumps blood through the body? 2. Which organ breaks down damaged red blood cells? 3. What is the liquid portion of blood? 4. What blood vessels carry blood to the heart? 5. What is the process of transferring blood from one person to another? 6. What is the name of the wall of tissue that separates the sides of the heart? 7. What blood vessels carry blood away from the heart? 8. What body system absorbs fluid in the body that leeches out of cells? 9. Where are red blood cells produced? 10. What type of blood lacks proteins on the red blood cells? 11. What system transports oxygen and nutrients to all parts of the body? 12. What is the largest blood vessel in the body? 13. What do white blood cells do? 14. What is the substance that stops bleeding by trapping blood cells and plasma? 15. What controls the heart’s rhythm? 16. What is the iron-containing protein found in blood? 17. What type of blood vessels allow nutrients and oxygen to pass through its walls? 18. What disease is the most common cause of heart attacks in adults? 19. In what body system do white blood cells mature? 20. What circulatory disease is known as a silent killer because it has no symptoms?