Heart dissection

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Across
  1. 1. The hard white layer surrounding the heart
  2. 3. The liquid that's pumped by the heart.
  3. 5. The best instrument to cut through chunks of tissue
  4. 7. Part of the heart that close to stop blood flowing the wrong way.
  5. 8. Blood vessels that bring blood back to the heart
  6. 9. The purple soft areas of the heart
Down
  1. 2. The string-like threads inside the heart.
  2. 4. Blood vessels that carry blood away from the heart.
  3. 6. Very sharp knife like instrument