The nervous system crossword

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Across
  1. 1. A small gap between two neurones, which a chemical message crosses
  2. 4. These actions do not involve the brain
  3. 7. These specialised cells carry electrical messages away from the central nervous system
  4. 9. A change in the environment
Down
  1. 2. A muscle or a gland
  2. 3. These specialised cells carry electrical messages towards the central nervous system
  3. 5. Keeping conditions inside the body the same
  4. 6. The central nervous system is made up of the brain and ______ ____
  5. 8. These are found in sense organs and detect a stimulus