Across
- 2. the scientific word for a muscle tensing
- 3. the tube that connects the mouth to the lungs
- 5. something made of two or more different elements chemically bonded
- 7. the bones that protect your lungs and heart
- 9. the organ where gas exchange happens
Down
- 1. the branches inside the lungs
- 4. depressant that contains ethanol
- 6. sheet of muscle that helps to push air in and out of lungs
- 8. the part of your lungs where oxygen enters the blood