Across
- 1. involuntary muscle
- 3. wind pipe
- 4. this system excretes waste
- 7. this body system produces blood cells
- 8. my job is to attach bone to bone
- 9. I am a muscle that contracts and relaxes as you breath
- 11. air sac
- 13. I am a system that can send signals the fingers
Down
- 2. I cushion the surface of the bones
- 3. my job is to attach bone to muscle
- 5. this system cushions internal organs
- 6. this prefix means skin
- 10. most muscles work in this
- 12. the gas my blood likes