Respiratory System :)

1234567
Across
  1. 2. Hollow cavities in the head that aid in breathing
  2. 3. The air sacs in the lungs
  3. 5. The tubes that deliver oxygen into the lungs
  4. 6. The chambers of the lungs
  5. 7. The place in which the lungs and heart live
Down
  1. 1. The thin muscle below your lungs
  2. 4. Our favorite little meat flap that keeps us from choking