Heart, Blood and Respiration

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Across
  1. 2. The muscle underneath the lungs
  2. 5. A group of cells in the right atrium that control how often the heart beats
  3. 6. These carry deoxygenated blood back to the heart
  4. 8. The sugar broken down in respiration
  5. 10. The capillary wall is _______ cell thick
  6. 11. The main artery in the body
  7. 12. The gas we breathe in
Down
  1. 1. These help prevent backflow
  2. 3. These take blood away from the heart
  3. 4. Respiration with oxygen
  4. 7. The __________ artery and vein connect the heart to the lungs
  5. 9. When you receive a new heart from someone else to replace your faulty one