The "Cardio"

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Across
  1. 2. of the heart are composed of the cardiac muscle.
  2. 7. contains blood on the right side.
  3. 8. what have wall one cell thick.
  4. 10. Direction blood flow in.
  5. 12. what ensure blood flow one direction.
Down
  1. 1. contain blood on the left side.
  2. 3. carry blood away from the heart.
  3. 4. what separates the two sides.
  4. 5. has thick walls.
  5. 6. has thin walls.
  6. 9. consist of how many chambers.
  7. 11. carry blood to the heart.